View source for 400-series highways

{{Short description|Ontario freeway network}}
{{Distinguish|Ontario Highway 400}}
{{For|the 400-series highways in British Columbia|400-series highways (British Columbia)}}
{{Use mdy dates|date=July 2024}}
{{featured list}}
{{infobox state highway system
| country    = CAN
| type       = Fwy
| title      = 400-series highways
| shields    = {{infobox road/shieldmain/CAN|province=ON|type=Hwy|route=403}} {{infobox road/shieldmain/CAN|province=ON|type=Hwy|route=QEW}}
| caption    = [[Highway shield|Highway markers]] for Highway&nbsp;403 and the Queen Elizabeth Way
| map        = 400-series highways map.svg
| map_notes  = The current 400-series Highway network in [[Southern Ontario]]
| map_alt    =
| maint      = [[Ministry of Transportation of Ontario]] (MTO)
| length_km  = 1997.3
| length_ref = <ref name="km">{{cite web |title = Annual Average Daily Traffic (AADT) counts |author = Ministry of Transportation of Ontario |author-link = Ministry of Transportation of Ontario |publisher = Government of Ontario |year = 2010 |url = http://www.raqsb.mto.gov.on.ca/techpubs/TrafficVolumes.nsf/tvweb?OpenForm&Seq=5 |access-date = March 29, 2016 |archive-url = https://web.archive.org/web/20110706192209/http://www.raqsb.mto.gov.on.ca/techpubs/TrafficVolumes.nsf/tvweb?OpenForm&Seq=5 |archive-date = July 6, 2011 |url-status = dead }}</ref>
| formed     = {{start date|1952|07|01}}
| label1     = [[Provincial highway|Provincial]]
| field1     = Ontario Highway 4XX
| links      = ON
}}
The '''400-series highways''' are a network of [[controlled-access highway]]s in the [[Canada|Canadian]] province of [[Ontario]], forming a special subset of the [[Ontario Provincial Highway Network|provincial highway system]]. They are analogous to the [[Interstate Highway System]] in the [[United States]] or the [[Autoroutes of Quebec|Autoroute system]] of neighbouring [[Quebec]], and are regulated by the [[Ministry of Transportation of Ontario]] (MTO). The 400-series designations were introduced in 1952, although Ontario had been constructing divided highways for two decades prior. Initially, only Highways&nbsp;[[Ontario Highway 400|400]], [[Ontario Highway 401|401]] and [[Ontario Highway 402|402]] were numbered; other designations followed in the subsequent decades. To this day, not all [[List of controlled-access highways in Ontario|controlled-access highways in Ontario]] are a part of the 400-series highway network. The network is situated almost entirely in [[Southern Ontario]], although [[Ontario Highway 400|Highway 400]] extends into the more remote [[Northern Ontario|northern]] portion of the province.

Modern 400-series highways have high design standards, [[speed limit]]s of {{convert|100|km/h|mph}}, with a {{convert|110|km/h|mph}} limit on select stretches, and various collision avoidance and traffic management systems. The design of 400-series highways has set the precedent for a number of innovations used throughout [[North America]], including the [[partial cloverleaf interchange|parclo interchange]] and a modified [[Jersey barrier]] design known as the Ontario Tall Wall. As a result, they currently experience one of the lowest accident and fatality rates comparative to traffic volume in North America.

{{TOC limit|2}}

== History ==
When the 400-series designations were first applied to Ontario freeways in 1952,<ref name="series400">{{cite news |title = Search Engine: Highway Mysteries Solved |first = Karena |last = Walter |work = The Niagara Falls Review |date = February 21, 2014 |url = http://www.stcatharinesstandard.ca/2014/02/21/search-engine-highway-mysteries-solved |access-date = December 17, 2015 |url-status = dead |archive-url = https://web.archive.org/web/20151222082645/http://www.stcatharinesstandard.ca/2014/02/21/search-engine-highway-mysteries-solved |archive-date = December 22, 2015 }}</ref>
several divided highways had already been opened in Southern Ontario.<ref name="1953map">{{cite map |title = Ontario Road Map |first = C.P. |last = Robins |publisher = Ontario Department of Highways |year = 1952 |section = Q28–U41 }}</ref>
Originally inspired by German [[Reichsautobahn|Autobahn]]s, Minister of Highways [[Thomas McQuesten]] planned a network of "Dual Highways" across the southern half of the province during the 1930s.<ref>{{cite news |title = Hopes to Improve Roads |work = The Gazette |location = Montreal |date = February 18, 1936 |page = 14 |url = https://news.google.com/newspapers?id=b74tAAAAIBAJ&dq=mcqueston%20highway&pg=3117%2C2124256 |access-date = February 9, 2010 |archive-date = October 19, 2021 |archive-url = https://web.archive.org/web/20211019192714/https://news.google.com/newspapers?id=b74tAAAAIBAJ&dq=mcqueston+highway&pg=3117%2C2124256 |url-status = live }}</ref>{{sfnp|Stamp|1987|pp=11–12|ps=.}}
The [[Queen Elizabeth Way]] (QEW) was first, an upgrade to the partially constructed [[The Middle Road|Middle Road]] in 1934.<ref name="globeandmail">{{cite news |title = Remember That 'Little Four-Lane Freeway?' |last = English |first = Bob |work = The Globe And Mail |location = Toronto |date = March 16, 2006 |quote = ...the freeway concept was promoted by Hamiltonian Thomas B. McQuesten, then the highway minister. The Queen Elizabeth Way was already under construction, but McQuesten changed it into a dual-lane divided highway, based on Germany's new autobahns. }}</ref>
McQuesten also sought out the economic opportunities that came with linking Toronto to [[Detroit]] and [[New York (state)|New York state]] by divided roadways with interchanges at major crossroads. Although he no longer served as Minister of Highways by the onset of [[World War II]], his ambitious plans would come to fruition in the following decades as Highways 400, 401, 402, 403 (between Woodstock and Hamilton), and 405.{{sfnp|Stamp|1987|p={{page needed|date=July 2020}}|ps=.}}

The construction boom following the war resulted in many new freeway construction projects in the province. The Toronto–Barrie Highway (Highway&nbsp;400), Trans-Provincial Highway (Highway&nbsp;401),<ref name="JShragge">{{cite web |title = Highway 401: The Story |last = Shragge |first = John G. |year = 2007 |url = http://www.roadscholar.on.ca/lateststory.html |access-date = February 12, 2010 |archive-url = https://web.archive.org/web/20080328001341/http://www.roadscholar.on.ca/lateststory.html |archive-date = March 28, 2008 }}</ref>
a short expansion of Highway&nbsp;7 approaching the [[Blue Water Bridge]] in Sarnia (Highway&nbsp;402),<ref name="Christina heritage">{{cite book |type = Report |title = Heritage Impact Assessment: Christina Street Bridge over Highway 402, Sarnia |author = Built Heritage, Cultural Landscape and Planning Section |publisher = Archaeological Services Inc |date = January 2006 |chapter = 2.0 Background History |page = 4 |chapter-url = http://www.historicbridges.org/concrete/christina/historical.pdf |access-date = January 6, 2014 |archive-date = September 23, 2020 |archive-url = https://web.archive.org/web/20200923055721/https://historicbridges.org/concrete/christina/historical.pdf |url-status = live }}</ref>
and an expansion of Highway&nbsp;27 (eventually designated as Highway 427 by the mid-1970s) into part of the Toronto Bypass were all underway or completed by the early 1950s.<ref name="JShragge" /> Seeking a way to distinguish the controlled-access freeways from the existing two-lane King's Highways, the Department of Highways created the 400-series designations in 1952. By the end of the year, Highway&nbsp;400, 401, and 402 were numbered, although they were only short stubs of their current lengths.<ref name="series400" /> Highway&nbsp;401 was assembled across the province in a patchwork fashion,<ref name="JShragge" />
becoming fully navigable between Windsor and the Quebec border on November&nbsp;10, 1964;<ref name="openDates">{{harvp|Ministry of Transportation and Communications|1972|pp=8–9}}.</ref>
Highway&nbsp;400 was extended north to [[Coldwater, Ontario|Coldwater]] on Christmas Eve 1959;<ref>{{cite news |title = Open 400 Link to Coldwater |work = The Toronto Star |date = December 24, 1959 |page = 18 |quote = The new, 22-mile extension from south of Crown Hill to Coldwater will be ready for traffic this afternoon. }}</ref>
Highway&nbsp;402 was extended to London between 1972 and 1982.<ref name="begin">{{cite book |title = Highway Construction Program: King's and Secondary Highways |publisher = Ministry of Transportation and Communications |year = 1972–1973 |page = xi }}</ref><ref name="ceremony">{{cite book |title = Annual Report |publisher = Ministry of Transportation and Communications |year = 1982–1983 |page = 76 |edition = Construction }}</ref>

In addition to this network backbone, plans for additional 400-series highways were initiated by the late 1950s, comprising the Chedoke Expressway (Highway&nbsp;403) through [[Hamilton, Ontario|Hamilton]];<ref name="planning">{{cite book |type = Report |title = Annual Report for the Fiscal Year |publisher = Ontario Department of Highways |date = March 31, 1958 |url = https://books.google.com/books?id=6f8iAQAAIAAJ&q=C.A.H+403 |access-date = July 25, 2010 }}</ref>
the [[Don Valley Parkway]] Extension (Highway&nbsp;404) northward from the soon-to-be constructed Toronto expressway;<ref name="plan">{{cite book |type = Report |title = Don Valley Parkway Extension, Highway 401 to Steeles Avenue |publisher = Desjardines |year = 1957 }}</ref>
Highway&nbsp;405 to connect with the American border near [[St. Catharines]];<ref>{{cite news |title = Above the Regular Budget |work = The Ottawa Citizen |date = July 31, 1958 |page = 7 |url = https://news.google.com/newspapers?id=uT4vAAAAIBAJ&dq=hamilton%20expressway%20toronto&pg=4732%2C2879605 |access-date = October 20, 2010 |archive-date = August 14, 2022 |archive-url = https://web.archive.org/web/20220814223431/https://news.google.com/newspapers?id=uT4vAAAAIBAJ&dq=hamilton%20expressway%20toronto&pg=4732%2C2879605 |url-status = live }}</ref>
Highway&nbsp;406 south from St. Catharines to [[Welland]];<ref>{{cite book |title = Annual Report |publisher = Department of Highways |date = March 31, 1961 |url = https://books.google.com/books?id=ngAjAQAAIAAJ&q=%22Highway%20406%22 |access-date = July 29, 2011 }}</ref>
Highway&nbsp;407 encircling the Greater Toronto Area (GTA), though not built for another 40 years;<ref name="suburbs">{{cite book |title = The Shape of the Suburbs: Understanding Toronto's Sprawl |first = John |last = Sewell |publisher = University of Toronto Press |year = 2009 |page = 72 |isbn = 978-0-8020-9884-9 |url = https://books.google.com/books?id=dFA2YUVA57wC&q=%22Highway+403%22&pg=PA72 |access-date = July 1, 2010 }}</ref>
Highway&nbsp;409 to connect Highway&nbsp;401 with [[Toronto Pearson International Airport|Toronto International Airport]];<ref>{{cite book |title = Malton: Farms to Flying |first = Kathleen A. |last = Hicks |publisher = Friends of the Mississauga Library System |year = 2006 |pages = 208–209 |section = Road Controversy - 1968 |isbn = 0-9697873-9-1 |url = http://www.mississauga.ca/file/COM/9634_MaltonBook_PartFour.pdf |access-date = April 4, 2010 |archive-date = November 25, 2020 |archive-url = https://web.archive.org/web/20201125072743/https://www.mississauga.ca/file/COM/9634_MaltonBook_PartFour.pdf |url-status = live }}</ref>
and The Queensway (Highway&nbsp;417) through Ottawa.<ref>{{cite web |title = The Queensway Began with a Royal Blast: Flashback to 1957. |first = Peter |last = Robertson |publisher = Carlington Community Association |url = http://www.carlingtoncommunity.org/?p=1492 |access-date = December 17, 2015 |archive-url = https://web.archive.org/web/20120426061730/http://www.carlingtoncommunity.org/?p=1492 |archive-date = April 26, 2012 }}</ref>
The first sections of these freeways were opened in 1963,{{sfnp|Ontario Department of Highways|1970|p=11|ps=.}}
1977,<ref name="1976report">{{cite book |type = Report |title = Construction Program: King's and Secondary Highways |publisher = Ministry of Transportation and Communications |year = 1976–1977 |page = XV }}</ref>
1963,{{sfnp|Ontario Department of Highways|1970|p=11|ps=.}} 1965,{{sfnp|Ontario Department of Highways|1970|p=12|ps=.}}
1997,<ref name="407dates">{{cite book |type = Report |title = Settlement of Claim of Richard Prendiville |publisher = Ontario Superior Court of Justice |date = December 12, 2001 |page = 7 |url = http://www.kmlaw.ca/site_documents/011240_SOC_18dec01.pdf |access-date = December 17, 2015 |archive-url = https://web.archive.org/web/20140727041251/http://www.kmlaw.ca/site_documents/011240_SOC_18dec01.pdf |archive-date = July 27, 2014 }}</ref>
1974,<ref>{{cite book |type = Report |title = Construction Program: King's and Secondary Highways |publisher = Ministry of Transportation and Communications |year = 1976–1977 |page = XIV }}</ref>
and 1960,<ref name="gloucester">{{cite book |title = A Historical Timeline for the Township of Gloucester |first = Glenn |last = Clark |publisher = The Gloucester Historical Society |date = April 14, 2012 |url = http://www.gloucesterhistory.com/history.html |access-date = July 1, 2012 |archive-date = August 21, 2012 |archive-url = https://web.archive.org/web/20120821202050/http://www.gloucesterhistory.com/history.html |url-status = live }}</ref>
respectively.

Throughout the 1960s and 1970s, additional freeways were planned or built, including Highway&nbsp;427 in Toronto,<ref name="assumed427"/>
Highway&nbsp;403 through Mississauga,<ref>{{cite news |title = Drivers Will Wait Years Before Relief from QEW Jams |first = Thomas |last = Coleman |work = The Globe and Mail |location = Toronto |date = July 12, 1975 |pages = 5 }}</ref>
Highway&nbsp;410 north to Brampton and Highway&nbsp;416 to connect Highways&nbsp;401 and 417.<ref name="teh">{{cite book |type = Report |title = The History of Toronto's Unfinished Expressway System |publisher = Energy Probe<!-- Note: Strikingly familiar to the former Get Toronto Moving Tranportation plan. --> |date = April 5, 2009 |url = http://ep.probeinternational.org/2009/04/05/history-torontos-unfinished-expressway-system/ |access-date = January 23, 2012 |archive-date = September 19, 2020 |archive-url = https://web.archive.org/web/20200919092827/https://ep.probeinternational.org/2009/04/05/history-torontos-unfinished-expressway-system/ |url-status = live }}</ref><ref>{{cite news |title = New 45-Mile Highway to Link Ottawa with 401 |work = The Globe and Mail |location = Toronto |date = November 14, 1967 |page = 4 }}</ref>
Highway&nbsp;420 was designated in Niagara Falls,<ref name="series400" /><ref>{{cite book |type = Report |title = Highway Construction Program 1972-73 |publisher = Ministry of Transportation and Communications |date = April 1972 |section = Queen Elizabeth Way - Hamilton to Fort Erie |page = xv }}</ref>
though it had been built as part of the QEW in 1941.{{sfnp|Stamp|1992|p=129|ps=.}} Other major works included the skyway bridges along the QEW and the expansion of Highway&nbsp;401 through most of Toronto into twelve-lane [[collector–express]] systems.<ref name="JShragge" />{{sfnp|Stamp|1987|pp=59–61|ps=.}}<ref>{{cite book |type = Report |title = Annual Report |publisher = Department of Highways |date = March 31, 1964 |section = Chronology |page = 296 }}</ref>

By the mid-1980s, the network had more-or-less taken its current shape, with only Highways&nbsp;407, 412, 416 and 418 yet to be built.<ref>{{cite map |title = Ontario Road Map |author = Cartography Section |publisher = Ministry of Transportation and Communications |year = 1986 }}</ref><ref name="2014map">{{cite map |title = Ontario Road Map |author = Cartography Section |publisher = Ministry of Transportation of Ontario |year = 2014–2015 }}</ref>
Instead, emphasis was placed on expanding existing routes to accommodate increasing traffic volumes.<ref name="suburbs" /> However, extensions of Highway&nbsp;400 towards [[Parry Sound, Ontario|Parry Sound]],<ref name="PStoPS">{{cite web |title = Highway 69 Four-Laning Port Severn to Parry Sound |author = Ministry of Transportation of Ontario |publisher = Government of Ontario |date = May 2000 |url = http://www.mto.gov.on.ca/english/traveller/highway69/images/highway69.pdf |archive-url = https://web.archive.org/web/20000823222037/http://www.mto.gov.on.ca/english/traveller/highway69/images/highway69.pdf |url-status = dead |archive-date = August 23, 2000 |access-date = December 27, 2011 }}</ref>
Highway&nbsp;403 between [[Woodstock, Ontario|Woodstock]] and Hamilton,<ref name="1989c">{{cite journal |title = Provincial Highways Construction Projects |author = Transportation Capital Branch |journal = Northern Transportation, Construction Projects |publisher = Ministry of Transportation |year = 1991–1992<!-- May 1991 --> |page = 7 |issn = 0714-1149 }}</ref>
Highway&nbsp;404 towards [[Newmarket, Ontario|Newmarket]],<ref name="Davis">{{cite news |title = Ontario Studies Plan to Extend Highway 404 Farther North |first = Brian |last = Dexter |work = The Toronto Star |date = October 25, 1989 |department = News |page = A8 }}</ref>
and Highway&nbsp;427 towards Vaughan were underway.<ref>{{cite book |type = Report |title = Provincial Highways Construction Projects |publisher = Ministry of Transportation |year = 1989–1990 |page = 13 |issn = 0714-1149 }}</ref>
By the end of the decade, construction of Highway&nbsp;407 and Highway&nbsp;416 had begun,<ref name="suburbs" /><ref>{{cite book |type = Report |title = Northern Transportation Construction Projects 1988–89 |author = Transportation Capital Branch |publisher = Ministry of Transportation of Ontario |date = May 1991 |page = 16 |issn = 0714-1149 }}</ref>
and Highway&nbsp;410 was expanded from two to four lanes.<ref>{{cite journal |title = Provincial Highways Construction Projects |author = Transportation Capital Branch |journal = Northern Transportation, Construction Projects |publisher = Ministry of Transportation and Communications |year = 1986–1987<!-- April 1986 --> |page = XII |issn = 0714-1149 }}</ref>

Highways&nbsp;407 and 416 opened in the late 1990s.<ref name="407dates" /><ref name="opened416"/>
Until early 2015, Highways&nbsp;407 and 416 were the most-recently designated (and constructed) freeways in Ontario.  This has changed with the construction of [[Ontario Highway 412|Highways&nbsp;412]] and [[Ontario Highway 418|418]].  In addition to these new additions to the 400-series network, several extensions of existing freeways have been built or are underway,<ref name="2014map" /> including Highway&nbsp;410 north of Brampton in 2009,<ref>{{cite news |title = Hwy 410 Extension Causing Confusion |first = Heather |last = Abrey |publisher = North Peel Media Group |work = Caledon Enterprise |date = November 20, 2009 |url = http://www.caledonenterprise.com/news-story/1368052-hwy-410-extension-causing-confusion/ |access-date = December 17, 2015 |archive-date = September 17, 2020 |archive-url = https://web.archive.org/web/20200917191331/https://www.caledonenterprise.com/news-story/1368052-hwy-410-extension-causing-confusion/ |url-status = live }}</ref>
Highway&nbsp;400 to north of Parry Sound in 2010,<ref name="nobel">{{cite news |title = $177-Million Section of Highway Now Open |first = Cameron |last = Ginn |publisher = Metroland Media Group |work = Cottage Country Now |date = October 27, 2010 |url = http://www.muskokaregion.com/news-story/3646903--177-million-section-of-highway-now-open/ |access-date = December 17, 2015 |archive-date = September 25, 2020 |archive-url = https://web.archive.org/web/20200925130503/https://www.muskokaregion.com/news-story/3646903--177-million-section-of-highway-now-open/ |url-status = live }}</ref>
Highway&nbsp;417 to [[Arnprior, Ontario|Arnprior]] in 2012,<ref name="Arnprior">{{cite news |title = Highway 417 opens at Arnprior |first = Sean |last = Chase |publisher = Canoe Sun Media |work = The Pembroke Observer |date = November 30, 2012 |url = http://www.thedailyobserver.ca/2012/11/30/highway-417-opens-at-arnprior |access-date = December 2, 2012 |archive-date = June 27, 2018 |archive-url = https://web.archive.org/web/20180627182926/http://www.thedailyobserver.ca/2012/11/30/highway-417-opens-at-arnprior |url-status = live }}</ref>
Highway&nbsp;404 to [[Keswick, Ontario|Keswick]] in 2014,<ref>{{cite news |title = Highway 404 Extension Opens |first = Dave |last = Bradley |work = NewsTalk 1010 |date = September 17, 2014 |url = http://www.newstalk1010.com/news/2014/09/17/highway-404-extension-opens |access-date = September 17, 2014 |archive-date = December 23, 2014 |archive-url = https://web.archive.org/web/20141223050831/http://www.newstalk1010.com/news/2014/09/17/highway-404-extension-opens |url-status = live }}</ref>
Highway&nbsp;401 through Windsor in 2015,<ref>{{cite news |title = Newsroom: Highway 401 Section of the New Rt. Hon. Herb Gray Parkway Now Complete |publisher = Ministry of Transportation |work = News.Ontario.ca |date = November 20, 2015 |url = https://news.ontario.ca/mto/en/2015/11/new-rt-hon-herb-gray-parkway-in-windsor-now-complete.html |access-date = November 21, 2015 |archive-date = July 14, 2017 |archive-url = https://web.archive.org/web/20170714135355/https://news.ontario.ca/mto/en/2015/11/new-rt-hon-herb-gray-parkway-in-windsor-now-complete.html |url-status = live }}</ref>
and four-laning Highway&nbsp;406 to Welland in late 2015.<ref>{{cite news |title = 406 Widening Underway |first = Paul |last = Forsyth |publisher = Metroland Media |work = Niagara This Week |date = August 19, 2011 |url = http://www.niagarathisweek.com/news-story/3260291-406-widening-underway/ |access-date = December 17, 2015 |archive-date = September 17, 2020 |archive-url = https://web.archive.org/web/20200917153542/https://www.niagarathisweek.com/news-story/3260291-406-widening-underway/ |url-status = live }}</ref>

== Design standards ==
The 400-series highways always have a minimum 4 lane cross-section with grade separation at all junctions. Interchanges tend to be spaced at least 1.5 kilometres apart in urban areas unless  there are basket weave ramps or collector lanes to facilitate shorter merge distances. In rural areas, interchanges tend to be spaced at least 3 kilometres apart, although exceptions exist. When the cross-section of highway is larger than 10 lanes, the road is usually arranged into a [[local–express lanes|local–express lane]] system, which exist on sections of Highways 400, 401, 403, 404 and 427. On all but a few interchanges in the whole system, ramps merge freely on the highway except if there are [[ramp meter]]s in use, and stop or yield controlled ramps are rare. An interchange with stop-controlled ramps onto Highway 400 at Canal Road is currently scheduled for replacement.

While older freeways have some lapses in safety features, contemporary 400-series highways have [[design speed]]s of {{convert|130|km/h|mph|0|abbr=on}}, [[Speed limits in Canada|speed limit]]s ranging from {{convert|80|km/h|mph|abbr=on|0}} to {{convert|110|kph|abbr=on}}, various collision avoidance and traffic management systems, and several design standards adopted throughout North America.<ref>{{cite news |title = An Expressway in Name Only |first = Nancy |last = Revie |work = The Guelph Mercury |date = September 19, 2005 |page = A9 }}</ref>
Of note are the [[Ontario Tall Wall]] median barrier and the [[Partial cloverleaf interchange|Parclo A-4]] interchange design, the latter which became standard in the design for the widening of Highway&nbsp;401 through Toronto in 1962. The [[Institute of Traffic Engineers]] subsequently recommended this design to replace the cloverleaf interchange throughout North America.<ref>{{cite book |type = Report |title = Proceedings ... Annual Meeting |publisher = Institute of Traffic Engineers |year = 1962 |pages = 100–103 }}</ref><ref>{{cite web |title = Partial Cloverleaf Interchange (Parclo) |publisher = The Canadian Design Resource |url = http://canadiandesignresource.ca/transportation/partial-cloverleaf-interchange-parclo/ |access-date = June 4, 2015 |archive-date = March 17, 2015 |archive-url = https://web.archive.org/web/20150317074644/http://www.canadiandesignresource.ca/transportation/partial-cloverleaf-interchange-parclo/ |url-status = live }}</ref>
Ontario highways rank fourth in North America for fatality rates, with 0.61 fatalities per 10,000 licensed drivers in 2017. However, this also includes two-lane provincial highways.<ref>{{cite book |type = Report |title = Ontario Road Safety Annual Report |author = ((Road Safety Policy Office - Vehicles)) |publisher = Government of Ontario |year = 2017 |page = 21 |chapter = Overview |chapter-url = http://www.mto.gov.on.ca/english/publications/pdfs/ontario-road-safety-annual-report-2017.pdf |access-date = March 7, 2021 |issn = 1710-2480 |archive-date = March 17, 2021 |archive-url = https://web.archive.org/web/20210317022022/http://www.mto.gov.on.ca/english/publications/pdfs/ontario-road-safety-annual-report-2017.pdf |url-status = live }}</ref>
On May 1, 2019, the government of Ontario was looking towards raising the speed limits of the 400-series highways up to {{convert|120|km/h|mph|abbr=on|}} [[Jeff Yurek]], Transportation Minister at that time had stated that "The 400-series highways were built for, I believe, a speed limit of 120 km/h safely."<ref>{{Cite web |url = https://globalnews.ca/news/5226562/ontario-proposing-raising-speed-limits-400-series-highways/ |title = Ontario to Look At Raising Speed Limits Across 400-Series Highways |first = Gabby |last = Rodrigues |date = May 1, 2019 |website = Global News |access-date = May 6, 2019 |archive-date = May 6, 2019 |archive-url = https://web.archive.org/web/20190506030237/https://globalnews.ca/news/5226562/ontario-proposing-raising-speed-limits-400-series-highways/ |url-status = live }}</ref>
A {{convert|110|kph|abbr=on}} trial was set up on three stretches of highways on September 26, 2019, to test the viability of increasing speed limits.<ref>{{cite web |title = Consultation: Speed Limits on Ontario Highways |url = https://www.ontario.ca/page/consultation-speed-limits-ontario-highways |publisher = Ministry of Transportation of Ontario |access-date = March 7, 2021 |archive-date = December 31, 2020 |archive-url = https://web.archive.org/web/20201231175550/https://www.ontario.ca/page/consultation-speed-limits-ontario-highways |url-status = live }}</ref> 
The three trialed sections along with three more sections were permanently changed to the higher speed limit on April 22, 2022, and two more sections were trialed.<ref>{{cite press release |first1 = Dakota |last1 = Brasier |first2 = Simisola |last2 = Ikotun |date = March 29, 2022 |url = https://news.ontario.ca/en/release/1001886/ontario-raising-highway-speed-limits |title = Ontario Raising Highway Speed Limits |publisher = Ministry of Transportation of Ontario |access-date = July 13, 2024 }}</ref> The two trialed sections were made permanent along with 10 more sections on July 12, 2024.<ref>{{cite web |date = July 12, 2024 |url = https://www.ontario.ca/page/raising-speed-limits-ontario-highways |title = Raising Speed Limits on Ontario Highways |publisher = Ministry of Transportation of Ontario |access-date = July 13, 2024 }}</ref><ref>{{cite press release |first1 = Dakota |last1 = Brasier |first2 = Tanya |last2 = Blazina |date = April 24, 2024 |url = https://news.ontario.ca/en/release/1004476/ontario-raising-highway-speed-limits |title = Ontario Raising Highway Speed Limits |publisher = Ministry of Transportation of Ontario |access-date = July 13, 2024 }}</ref> On October 2, 2024, Premier [[Doug Ford]] mentioned in a press conference that he had directed Transportation Minister [[Prabmeet Sarkaria]] to raise the speed limit on all remaining 400-series highway sections “where it is safe to do so”.<ref>{{Cite web |last=Jones |first=Allison |date=October 2, 2024 |title=Ontario plans to raise speed limit on 400-series highways, premier says |url=https://ottawacitizen.com/news/ontario-raise-speed-limit-400-series-highways#:~:text=TORONTO%20%E2%80%94%20Ontario%20Premier%20Doug%20Ford,that%20first%20began%20in%202019. |access-date=November 2, 2024 |publisher=Ottawa Citizen |type=News Release}}</ref>

Conforming with the ''[[Manual on Uniform Traffic Control Devices]]'', Ontario utilizes green signs for guidance purposes, including distances to nearby interchanges and destinations.<ref name="OTM8">{{cite web |title = Ontario Traffic Manual Book 8: Guide and Information Signs – Volume 1 |author = Ministry of Transportation of Ontario |publisher = Government of Ontario |date = May 2010 |page = 18 |url = http://www.directtraffic.ca/wp-content/uploads/2014/02/Book-81.pdf |access-date = February 24, 2016 |archive-date = March 8, 2016 |archive-url = https://web.archive.org/web/20160308150328/http://www.directtraffic.ca/wp-content/uploads/2014/02/Book-81.pdf |url-status = dead }}</ref>
Generally, blue signage is used to list services and attractions at upcoming exits, known as [[Tourism-Oriented Directional Signing]].<ref>{{cite web |title = Tourism-Oriented Directional Signing (TODS) Program |author = Ministry of Tourism, Culture and Sport |publisher = Government of Ontario |date = November 23, 2015 |url = http://www.mtc.gov.on.ca/en/tourism/tods.shtml |access-date = February 24, 2016 |archive-date = September 28, 2017 |archive-url = https://web.archive.org/web/20170928032108/http://www.mtc.gov.on.ca/en/tourism/tods.shtml |url-status = live }}</ref>
However, several exceptions exist, notably blue guidance signage for toll highways such as [[Ontario Highway 407|Highway&nbsp;407]], in addition to the [[express-collector|collector lanes]] of highways.<ref name="OTM8" />
The baseline standard for the construction of or expansion to a freeway in Ontario is an [[Average annual daily traffic|average daily traffic count]] of 10,000 vehicles per day. However, other factors are considered as well, particularly future traffic volume forecasts. To promote economic development in a disadvantaged region (e.g., the current extension of Highway 400 to [[Northern Ontario]]), a 400-series highway may be built where the existing highway's traffic counts fall below 10,000.<ref>{{cite book |type = Report |title = Highway 69 Action Plan |author = Ministry of Northern Development and Mines |publisher = Government of Ontario |date = June 2005 |page = 3 |url = http://www.thepixelwarehouse.com/69_2006/pdf/2005_HWY69_ActionPlan_e.pdf |access-date = February 25, 2016 |url-status = dead |archive-url = https://web.archive.org/web/20140309201327/http://www.thepixelwarehouse.com/69_2006/pdf/2005_HWY69_ActionPlan_e.pdf |archive-date = March 9, 2014 }}</ref>

The MTO plans and finances the construction and maintenance of the King's Highway system, which includes the 400-series network.<ref>{{cite web |title = Highway Traffic Act |publisher = Government of Ontario |year = 2016 |url = https://www.ontario.ca/laws/statute/90h08 |access-date = May 8, 2016 |archive-date = November 22, 2009 |archive-url = https://web.archive.org/web/20091122043253/http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_90h08_e.htm |url-status = live }}</ref>
The system includes {{convert|1971.8|km}} of freeways. Highway&nbsp;401 is the longest freeway at {{convert|828.0|km}}, in addition to being the widest and busiest road in Canada. Highway&nbsp;420 is the shortest of the routes at {{convert|3.3|km}}.<ref name="km" />

There are four examples of 400 series standard highways in Ontario that are not signed as such. The [[Gardiner Expressway]] between Highway 427 and Parklawn Road was originally built as a section of QEW (Hwy 451<ref>{{Cite web |title=Queen Elizabeth Way (QEW) History - The King's Highways of Ontario |url=https://www.thekingshighway.ca/Queen_Elizabeth_Way.htm |access-date=2024-12-10 |website=www.thekingshighway.ca}}</ref>) and therefore is built to 400-series standards but lost its QEW designation after being downloaded to the City of Toronto. The section of [[Highway 7 (Ontario)|Highway 7]] between the town of [[Carleton Place]] and its junction with Highway 417 is also built to 400-series standards, but a 400-series designation has yet to be applied. [[Ontario Highway 69|Highway 69]] between Sudbury and Key River is built to 400-series standards in anticipation of it becoming part of Highway 400 once the {{convert|70|km|mi|adj=on}} gap between the two freeways is filled. [[Ontario Highway 115|Highway 115]] north of Highway 35/Highway115 concurrency and Peterborough is also built to 400-series standards, however a 400-series designation has yet to be applied. Most other freeways and expressways in Ontario that lack a 400-series designation have lower construction standards, lower design speeds and lower speed limits.

== High-occupancy vehicle lanes ==
[[File:400-series HOV lanes map.svg|thumbnail|left|Map showing locations of HOV lanes in the province as of September 2021]]

The MTO began planning for the use of [[high-occupancy vehicle]] (HOV) lanes with the HOV Opportunities Study, contracted to  [[McCormick Rankin]] in 2001. This led to the test trial of three HOV lanes in the GTA in December 2005: southbound Highway&nbsp;404 between Highway&nbsp;7 and Highway&nbsp;401, with a dedicated HOV ramp built to connect with westbound Highway&nbsp;401, and Highway&nbsp;403 in both directions between Highway&nbsp;407 and Highway&nbsp;401 in Mississauga.<ref>{{cite book |type = Report |title = Evaluating HOV Plans and Priorities – the Case of Expressways in the GTA |first1 = Goran |last1 = Nikolic |first2 = Rob |last2 = Pringle |publisher = Transportation Association of Canada |year = 2008 |pages = 2–4 |url = http://conf.tac-atc.ca/english/resourcecentre/readingroom/conference/conf2008/docs/k2/Pringle.pdf |access-date = January 1, 2016 |archive-date = December 22, 2015 |archive-url = https://web.archive.org/web/20151222081826/http://conf.tac-atc.ca/english/resourcecentre/readingroom/conference/conf2008/docs/k2/Pringle.pdf |url-status = live }}</ref>
Since then, HOV lanes have been opened on several 400-series freeways around the [[Golden Horseshoe]] and [[National Capital Region (Canada)|National Capital Region]]. In May 2007, the MTO introduced a multibillion-dollar Horseshoe Network Project, which included plans to incorporate HOV lanes into numerous 400-series highways.<ref name="hovplan">{{cite press release |title = McGuinty Government To Improve Commuters Lives With HOV Lane Network |author = Ministry of Transportation of Ontario |publisher = CNW Group |date = May 24, 2015 |url = http://www.newswire.ca/news-releases/mcguinty-government-to-improve-commuters-lives-with-hov-lane-network-533803981.html |access-date = January 1, 2016 |archive-url = https://web.archive.org/web/20160304082223/http://www.newswire.ca/news-releases/mcguinty-government-to-improve-commuters-lives-with-hov-lane-network-533803981.html |archive-date = March 4, 2016 |url-status = dead }}</ref>

By then, work was already advanced on several projects, including the northbound HOV lane on Highway&nbsp;404 (that opened on July&nbsp;23, 2007) and an HOV lane along both directions of Highway&nbsp;403 between Highway&nbsp;407 and Highway&nbsp;401. A third pair of HOV lanes has since been introduced to the QEW/403 through Oakville, and a fourth individual HOV lane travels eastbound on Highway&nbsp;417 from just west of [[Eagleson Road]] in [[Ottawa]] to just east of Moodie Drive.<ref name="hovplan" />

More than {{convert|450|km}} of HOV lanes are currently proposed for construction by 2040. Future plans include extending existing HOV lanes and introducing them to other 400-series freeways.<ref name="mto">{{cite web |title = Ontario's High Occupancy Vehicle Lane Network Plan for the 400-Series Highways in the Greater Golden Horseshoe |author = Ministry of Transportation of Ontario |publisher = Government of Ontario |url = http://www.mto.gov.on.ca/english/traveller/hov/plan2007.htm |archive-url = https://web.archive.org/web/20141018093151/http://www.mto.gov.on.ca/english/traveller/hov/plan2007.shtml |archive-date = October 18, 2014 |access-date = June 9, 2015 }}</ref>
{{As of|October 2014|lc=on}}, two projects have been confirmed: Highway&nbsp;410 between Highway&nbsp;401 and Queen Street in Brampton, and Highway&nbsp;427 between Highway&nbsp;409 and Highway&nbsp;7. The MTO has stated that HOV lanes will only be introduced through new construction and that no general-purpose lanes will be converted. The general goals of the project are to help increase highway efficiency (an HOV lane is claimed by the Ontario government to have the ability to move as many people as four general-purpose lanes),<ref name="mto"/> reduce congestion, conserve energy and help protect the environment.<ref>{{cite web |title = The Big Move - Strategy #3 - Improve the Efficiency of the Road and Highway Network |publisher = Metrolinx |url = http://www.metrolinx.com/thebigmove/en/strategies/strategy3.aspx |access-date = June 9, 2015 |archive-date = February 6, 2017 |archive-url = https://web.archive.org/web/20170206011636/http://www.metrolinx.com/thebigmove/en/strategies/strategy3.aspx |url-status = dead }}</ref>

During the [[2015 Pan American Games]] and [[2015 Parapan American Games]] held in [[Toronto]], several HOV lanes had their minimum requirements increased from two passengers to three, and some highways had their general-purpose lanes temporarily converted to HOV lanes to accommodate increased traffic. These temporary restrictions lasted from June&nbsp;29 to August&nbsp;18.<ref>{{cite news |title = HOV Lane Restrictions Now in Effect for Pan Am Games |first = David |last = Shum |date = June 29, 2015 |work = Global News |url = http://globalnews.ca/news/2081100/hov-lane-restrictions-now-in-effect-for-pan-am-games/ |access-date = August 22, 2015 |archive-date = September 11, 2018 |archive-url = https://web.archive.org/web/20180911012222/https://globalnews.ca/news/2081100/hov-lane-restrictions-now-in-effect-for-pan-am-games/ |url-status = live }}</ref>

2021 saw several new HOV lanes opened. The southbound HOV lane on Highway{{nbsp}}400 between King Road and Major Mackenzie Drive was opened on September{{nbsp}}11, 2021; while the northbound lane opened two months later on November{{nbsp}}11. The Highway{{nbsp}}427 extension, which opened on September{{nbsp}}18, included an HOV lane north of Finch Avenue.<ref>{{cite web |title = Adding More Lanes to Highway 400 to Keep People Moving |url = https://news.ontario.ca/en/release/45268/adding-more-lanes-to-highway-400-to-keep-people-moving |website = Ontario |access-date = July 22, 2021 |archive-date = July 22, 2021 |archive-url = https://web.archive.org/web/20210722025659/https://news.ontario.ca/en/release/45268/adding-more-lanes-to-highway-400-to-keep-people-moving |url-status = live }}</ref><ref>{{cite tweet |title = Excited to report that the new southbound HOV lanes on Highway 400 in the #KingTownship & #Vaughan community will open tomorrow! |first = Stephen |last = Lecce |author-link = Stephen Lecce |user = sflecce |number = 1436473186799980544 }}</ref><ref>{{cite news |title = Ontario Opens Highway 427 Expansion |publisher = Ministry of Transportation of Ontario |date = September 16, 2021 |url = https://news.ontario.ca/en/release/1000814/ontario-opens-highway-427-expansion |access-date = September 18, 2021 |archive-date = March 17, 2022 |archive-url = https://web.archive.org/web/20220317082614/https://news.ontario.ca/en/release/1000814/ontario-opens-highway-427-expansion |url-status = live }}</ref><ref>{{cite tweet |title = Northbound HOV lanes on Highway 400 in the Vaughan area open by tonight! |author = Ministry of Transportation of Ontario |author-link = Ministry of Transportation of Ontario |user = sflecce |number = 1458842103824498700 }}</ref>

=== Future HOV lanes ===
The following table lists planned expansions to the HOV network by 2040.<ref name="mto" /><ref name="hwyprogram">{{cite web |title = Ontario's highway programs |url = https://www.ontario.ca/page/ontarios-highway-programs |publisher = Ontario Ministry of Transportation |access-date = August 2, 2020 |date = May 28, 2020 |archive-date = March 7, 2022 |archive-url = https://web.archive.org/web/20220307021808/https://www.ontario.ca/page/ontarios-highway-programs |url-status = live }}</ref>
{| class="wikitable plainrowheaders"
|+ Near-term (anticipated completion by 2025)
|-
! scope = "col" | Highway
! scope = "col" | Starting location
! scope = "col" | Terminating location
! scope = "col" | General location
! scope = "col" | Status
|-
! scope = "row" | 400
| King Road
| Highway 9
| Region of York
| Lane construction underway, expected completion, 2025

|}
{| class="wikitable plainrowheaders"
|+ Long-term (2025–)
|-
! scope = "col" | Highway
! scope = "col" | Starting location
! scope = "col" | Terminating location
! scope = "col" | General location
|-
! scope = "row" | 400
| Langstaff Road
| Major Mackenzie Drive
| [[Regional Municipality of York]]
|-
! scope = "row" | 400
| Highway 9
| Highway 88/[[Bradford West Gwillimbury, Ontario|Bradford West Gwillimbury]]
| [[Regional Municipality of York, Ontario|Region of York]] and [[Simcoe County, Ontario|Simcoe County]]
|-
! scope = "row" | 401
| Regional Road 25
| Halton-Wellington Boundary
| [[Regional Municipality of Halton]]
|-
! scope = "row" | 401
| [[Highway 6]] South, Brock Road
| Highway 6 North
| [[Wellington County, Ontario|Wellington County]] and [[Guelph]]
|-
! scope = "row" | 401
| Townline Road
| Wellington Road 32
| [[Wellington, County, Ontario|Wellington County]] and [[Cambridge]]
|-
! scope = "row" | 404
| Stouffville Road
| Ravenshoe Road
| [[Regional Municipality of York, Ontario|Region of York]]
|-
! scope = "row" | QEW
| [[Red Hill Valley Parkway]]
| Highway 406
| [[Hamilton, Ontario|Hamilton]] and [[Regional Municipality of Niagara|Region of Niagara]]
|-
! scope = "row" | QEW
| 407/403
| Guelph Line
| [[Burlington, Ontario|Burlington]]
|-
! scope = "row" | QEW
| Trafalgar Road
| [[Highway 427]]
| [[Oakville, Ontario|Oakville]] and Mississauga
|}

== Planned extensions and new routes ==
{{sticky header}} 
{|class="wikitable sortable sticky-header-multi" style=text-align:center" style="margin:1em auto;"
|+
!Highway
!Type
!Length (km)
!Length (mi)
!Southern or western terminus
!Northern or eastern terminus
!Status
!Proposed Opening Date
!Notes
|-
|[[Highway 400 (Ontario)|Highway 400]]
|Extension<ref>{{Cite web |date = 2020 |title = Connecting the North: A Draft Transportation Plan for Northern Ontario |url = https://www.ontario.ca/page/connecting-north-draft-transportation-plan-northern-ontario |website = Province of Ontario |access-date = June 18, 2022 |archive-date = June 18, 2022 |archive-url = https://web.archive.org/web/20220618004020/https://www.ontario.ca/page/connecting-north-draft-transportation-plan-northern-ontario |url-status = live }}</ref>
|~138 
|~86
|[[Ontario Highway 559|Highway 559]] near [[Parry Sound, Ontario|Parry Sound]]
|[[Highway 17 (Ontario)|Highway 17]] in [[Greater Sudbury|Sudbury]]
|Partially Open / Under Construction
|Late 2020s
|Completed sections numbered as Highway 69
|-
|[[Ontario Highway 401|Highway 401]]
|Extension<ref>{{Cite web |date = 2022 |title = Project Overview |url = https://www.gordiehoweinternationalbridge.com/en/project-overview |access-date = June 8, 2022 |website = Gordie Howe International Bridge |archive-date = July 11, 2021 |archive-url = https://web.archive.org/web/20210711210903/https://www.gordiehoweinternationalbridge.com/en/project-overview |url-status = live }}</ref>
|~3
|~2
|[[Interstate 75 in Michigan|I-75]] in [[Detroit]]
|Ojibway Parkway in [[Windsor, Ontario|Windsor]]
|Unopened
|2025
|Part of [[Gordie Howe International Bridge]] Project
|-
|[[Ontario Highway 404|Highway 404]]
|Extension<ref>{{Cite web |date = 2022 |title = Connecting the GGH: A Transportation Plan for the Greater Golden Horseshoe |url = https://www.ontario.ca/page/connecting-ggh-transportation-plan-greater-golden-horseshoe |website = Province of Ontario |access-date = June 18, 2022 |archive-date = June 18, 2022 |archive-url = https://web.archive.org/web/20220618004026/https://www.ontario.ca/page/connecting-ggh-transportation-plan-greater-golden-horseshoe |url-status = live }}</ref>
|~31
|~19
|Regional Road 8 in [[Keswick, Ontario|Keswick]]
|[[Highway 12 (Ontario)|Highway 12]] north of [[Sunderland, Ontario|Sunderland]]
|Proposed
|Late 2020s
|
|-
|[[Ontario Highway 410|Highway 410]]
|Extension<ref name=":0">{{Cite web |date = April 2022 |title = Preferred Route Factsheet |url = https://www.highway413.ca/wp-content/uploads/2020/08/AECOM-Bulletin-AUG-07-2020-Final-web.pdf |access-date = June 8, 2022 |website = Highway 413 |archive-date = March 26, 2022 |archive-url = https://web.archive.org/web/20220326011309/https://www.highway413.ca/wp-content/uploads/2020/08/AECOM-Bulletin-AUG-07-2020-Final-web.pdf |url-status = live }}</ref>
|~3
|~2
|[[Ontario Highway 10|Highway 10]] in [[Brampton]]
|Future [[Ontario Highway 413|Highway 413]] north of [[Brampton]]
|Funded
|Late 2020s
|Part of the Highway 413 project
|-
|[[Ontario Highway 413|Highway 413]]
|New Route<ref name=":0" />
|~52
|~32
|[[Ontario Highway 401|Highway 401]] and [[Highway 407 (Ontario)|Highway 407]] in NW Mississauga
|[[Highway 400 (Ontario)|Highway 400]] north of [[Vaughan]]
|Funded
|Late 2020s
|
|-
|[[Ontario Highway 417|Highway 417]]
|Extension<ref>{{Cite web |date = 2022 |title = Connecting the East: A draft transportation plan for eastern Ontario |url = https://www.ontario.ca/page/connecting-east-draft-transportation-plan-eastern-ontario |website = Province of Ontario |access-date = June 18, 2022 |archive-date = June 18, 2022 |archive-url = https://web.archive.org/web/20220618004024/https://www.ontario.ca/page/connecting-east-draft-transportation-plan-eastern-ontario |url-status = live }}</ref>
|~16
|~10
|[[Highway 60 (Ontario)|Highway 60]] in [[Renfrew, Ontario|Renfrew]]
|Campbell Drive west of [[Arnprior]]
|Proposed
|Late 2020s
|
|-
|[[Ontario Highway 427|Highway 427]]
|Extension<ref name=":0" />
|~2
|~2
|Regional Road 25 south of [[Bolton, Ontario|Bolton]]
|Future [[Ontario Highway 413|Highway 413]] South of Bolton
|Funded
|Late 2020s
|Part of the Highway 413 project
|-
|"[[Bradford Bypass]]"
|New Route<ref>{{Cite web |date = 2020 |title = OVERVIEW - BRADFORD BYPASS |url = https://www.bradfordbypass.ca/overview/ |access-date = June 8, 2022 |website = Bradford Bypass |archive-date = May 24, 2022 |archive-url = https://web.archive.org/web/20220524204059/https://www.bradfordbypass.ca/overview/ |url-status = live }}</ref>
|~16
|~10
|Highway 400 near [[Bradford, Ontario|Bradford]]
|[[Ontario Highway 404|Highway 404]] south of [[Keswick, Ontario|Keswick]]                         
|Funded
|Late 2020s
|Intended to be a 400 series standard highway, designation is unclear. Construction began at the Yonge Street interchange in November 2022
|}

== Existing network ==
{{routelist top|local|unit=km}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 400
|local           = Toronto–Barrie Highway
|length_km       = 226.0
|terminus_a      = Maple Leaf Drive in Toronto<br /><small>(continues as [[Black Creek Drive]])</small>
|terminus_b      = {{jcon|Hwy|<!--17-->69|nosh=y}} in [[<!--Greater Sudbury-->Carling, Ontario|<!--Sudbury-->Carling]]
|established     = 1952-07-01
|established_ref = {{sfnp|Shragge|Bagnato|1984|pp=89–92|ps=.}}
|notes           = Scheduled for extension to [[Greater Sudbury|Sudbury]].{{sfnp|Shragge|Bagnato|1984|pp=89–92|ps=.}}
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 401
|local           = Macdonald–Cartier Freeway, Rt. Hon. Herb Gray Parkway, Highway of Heroes
|length_km       = 828.0
|terminus_a      = Ojibway Parkway in [[Windsor, Ontario|Windsor]]
|terminus_b      = [[Quebec Autoroute 20|A-20]] towards [[Montreal|Montreal, QC]]
|established     = 1952-07-01
|established_ref = {{sfnp|Shragge|Bagnato|1984|pp=89–92|ps=.}}
|notes           = Busiest highway in North America.<ref name="fhwa">{{cite book |type = Report |title = Long-Life Concrete Pavements in Europe and Canada |first = Hanna |last = Maier |publisher = Federal Highway Administration |date = October 9, 2007 |section = Chapter&nbsp;2 |url = https://international.fhwa.dot.gov/pubs/pl07027/llcp_07_02.cfm |access-date = May 1, 2010 |quote = The key high-volume highways in Ontario are the 400-series highways in the southern part of the province. The most important of these is the 401, the busiest highway in North America, with average annual daily traffic (AADT) of more than 425,000&nbsp;vehicles in 2004 and daily traffic sometimes exceeding 500,000&nbsp;vehicles. |archive-date = May 27, 2010 |archive-url = https://web.archive.org/web/20100527124628/http://international.fhwa.dot.gov/pubs/pl07027/llcp_07_02.cfm |url-status = live }}</ref> Scheduled for extension to [[Canada–United States border|American border]] following completion of the [[Gordie Howe International Bridge]].
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 402
|local           = 
|length_km       = 102.5
|terminus_a      = [[Interstate 69 in Michigan|I-69]]&nbsp;/ [[Interstate 94 in Michigan|I-94]] at [[Canada–United States border]] on [[Blue Water Bridge]] in [[Point Edward, Ontario|Point Edward]]
|terminus_b      = {{jcon|Hwy|401|nosh=y}} in [[London, Ontario|London]]
|established     = 1953-01-01
|established_ref = <ref name="Christina heritage"/>
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 403
|local           = Chedoke Expressway, Alexander Graham Bell Parkway
|length_km       = 125.2
|terminus_a      = {{jcon|Hwy|401|nosh=y}} near [[Woodstock, Ontario|Woodstock]]
|terminus_b      = {{jcon|Hwy|401|con=410|nosh=y}} in Mississauga
|established     = 1963-12-01
|established_ref = {{sfnp|Ontario Department of Highways|1970|p=11|ps=.}}
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 404
|local           = 
|length_km       = 50.1
|terminus_a      = {{jcon|Hwy|401|nosh=y}} / [[Don Valley Parkway|DVP]] in [[Toronto]]
|terminus_b      = {{jcon|York|8|nosh=y}} ([[Woodbine Avenue]]) in [[East Gwillimbury]]
|established     = 1977-01-01
|established_ref = <ref name="1976report" />
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 405
|local           = General Brock Parkway
|length_km       = 8.7
|terminus_a      = {{jcon|Hwy|QEW|city=St. Catharines|nosh=y}}
|terminus_b      = [[Interstate 190 (New York)|I-190]] at [[Canada–United States border]] on [[Queenston-Lewiston Bridge]] towards [[Lewiston, New York|Lewiston, NY]]
|established     = 1963-09-11
|established_ref = {{sfnp|Ontario Department of Highways|1970|p=11|ps=.}}
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 406
|local           = 
|length_km       = 26.0
|terminus_a      = East Main Street in [[Welland]]
|terminus_b      = {{jcon|Hwy|QEW|nosh=y}} in [[St. Catharines]]
|established     = 1965-12-07
|established_ref = {{sfnp|Ontario Department of Highways|1970|p=12|ps=.}}
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Both
|route           = 407
|local           = 
|length_km       = 151.4
|terminus_a      = {{jcon|Hwy|403|con=QEW|nosh=y}} in [[Burlington, Ontario|Burlington]]
|terminus_b      = {{jcon|Hwy|35|con=115|nosh=y}} in [[Clarington]]
|established     = 1997-06-07
|established_ref = <ref name="opened407">{{cite news |title = At Last — Opening Bell Tolls for the 407 |first1 = Bob |last1 = Mitchell |newspaper = The Toronto Star |date = June 6, 1997 |pages = A1, A6 }}</ref>
|notes           = Freeway divided into two sections: 407 ETR, with the latter tolled and privately operated, and Highway 407E;<ref name="length">{{cite web |title = Map / Toll Calculator |publisher = 407 ETR |date = February 1, 2014 |url = https://www.407etr.com/en/tolls/tolls/toll-calculator.html |access-date = December 17, 2015 |archive-date = February 2, 2021 |archive-url = https://web.archive.org/web/20210202160837/https://407etr.com/en/tolls/tolls/toll-calculator.html |url-status = live }}</ref> tolls removed on Highway 407E effective June 1, 2025
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 409
|local           = Belfield Expressway
|length_km       = 5.6
|terminus_a      = [[Toronto Pearson International Airport|Pearson Airport]] in [[Mississauga]]
|terminus_b      = {{jcon|Hwy|401|nosh=y}} in [[Toronto]]
|established     = 1978-08-25
|notes           = none
|established_ref = <ref name="opened409">{{cite news |title = New Shortcut Will Let Some 'Fly' to Airport |work = The Toronto Star |date = August 19, 1978 |department = Metro News |page = A6 |quote = Highway 409, a new shortcut to Toronto International Airport, opens next Friday }}</ref>
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 410
|local           = 
|length_km       = 20.3
|terminus_a      = {{jcon|Hwy|401|con=403|nosh=y}} in [[Mississauga]]
|terminus_b      = {{jcon|Hwy|10|[[Hurontario Street]]|nosh=y}} in [[Caledon, Ontario|Caledon]]
|established     = 1978-11-15
|established_ref = <ref name="opened1978">{{cite press release |title = Highway 410 Opens November 15 |author = Public and Safety Information Section |publisher = Ministry of Transportation and Communications |date = November 9, 1978 }}</ref>
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 412
|local           = West Durham Link
|length_km       = 10.0
|terminus_a      = {{jcon|Hwy|401|nosh=y}} in [[Whitby, Ontario|Whitby]]
|terminus_b      = {{jcon|Hwy|407|nosh=y}} in Whitby
|established     = 2016-06-20
|established_ref = <ref>{{cite news |title = UPDATE: Hwy. 407 From Pickering to Oshawa Opens June 20: Toll Free Until End of 2016 |first = Parvaneh |last = Pessian |work = Whitby This Week |date = June 17, 2016 |url = http://www.durhamregion.com/news-story/6728167-update-hwy-407-from-pickering-to-oshawa-opens-june-20-toll-free-until-end-of-2016/ |access-date = June 17, 2016 |archive-date = December 13, 2017 |archive-url = https://web.archive.org/web/20171213010400/https://www.durhamregion.com/news-story/6728167-update-hwy-407-from-pickering-to-oshawa-opens-june-20-toll-free-until-end-of-2016/ |url-status = live }}</ref>
|notes           = Route number assigned February&nbsp;5, 2015;<ref name="Numbered">{{cite web |title = New Highway Numbers |publisher = Highway 407 East |url = http://www.highway407east.com/spotlight/new-highway-numbers/ |archive-url = https://web.archive.org/web/20150419132510/http://www.highway407east.com/spotlight/new-highway-numbers/ |url-status = usurped |archive-date = April 19, 2015 |access-date = February 10, 2015 }}</ref> tolls removed effective April 5, 2022<ref name=removed>{{cite news |last1 = Alberga |first1 = Hannah |title = 'Unfair tolls': Ford officially scraps tolls on two Ontario highways |url = https://www.ctvnews.ca/toronto/article/unfair-tolls-ford-officially-scraps-tolls-on-two-ontario-highways/ |access-date = April 6, 2022 |work = CTV News Toronto |date = April 5, 2022 |language = en |archive-date = April 6, 2022 |archive-url = https://web.archive.org/web/20220406060958/https://toronto.ctvnews.ca/unfair-tolls-ford-officially-scraps-tolls-on-two-ontario-highways-1.5848552 |url-status = live }}</ref>
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 416
|local           = Veterans Memorial Highway
|length_km       = 76.4
|terminus_a      = {{jcon|Hwy|401|nosh=y}} towards [[Brockville, Ontario|Brockville]]
|terminus_b      = {{jcon|Hwy|417|nosh=y}} in [[Ottawa]]
|established     = 1999-09-23
|established_ref = <ref name="opened416">{{cite news |title = Ottawa Highway Link Opens |agency = Canadian Press |work = Toronto Star |date = September 24, 1999 |department = Ontario |page = A4 }}</ref>
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 417
|local           = Queensway, Trans-Canada Highway
|length_km       = 192.0
|terminus_a      = {{jcon|Hwy|17|nosh=y}} in [[Arnprior]]
|terminus_b      = [[Quebec Autoroute 40|A-40 (TCH)]] towards [[Montreal|Montreal, QC]]
|established     = 1971-01-01
|established_ref = <ref name="gloucester"/>
|notes           = Unlike most freeways, kilometre posts are numbered east to west.
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 418
|local           = East Durham Link
|length_km       = 12.8
|terminus_a      = {{jcon|Hwy|401|nosh=y}} in [[Clarington]]
|terminus_b      = {{jcon|Hwy|407|nosh=y}} in Clarington
|established     = 2019-12-09
|established_ref = <ref name="opened418">{{cite news |title = Extension of Ontario Hwy. 407, new Hwy. 418 open east of Toronto |newspaper = On-Site Magazine |date = December 9, 2019 |publisher = On-Site |url = https://www.on-sitemag.com/roads/extension-of-ontario-hwy-407-new-hwy-418-open-east-of-toronto/1003966229/ |access-date = December 11, 2019 |quote = An eastern extension of Ontario Hwy. 407 and a new toll road to connect the lengthened highway to nearby Hwy. 401 opened Dec. 9 on the outskirts of Toronto. |archive-date = December 12, 2019 |archive-url = https://web.archive.org/web/20191212074428/https://www.on-sitemag.com/roads/extension-of-ontario-hwy-407-new-hwy-418-open-east-of-toronto/1003966229/ |url-status = live }}</ref>
| notes          = Route number assigned February&nbsp;5, 2015;<ref name="Numbered" /> tolls removed effective April 5, 2022<ref name=removed/>
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 420
|local           = Niagara Veterans Memorial Highway
|length_km       = 3.3
|terminus_a      = {{jcon|Niagara|98|Montrose Road|nosh=y}}
|terminus_b      = [[U.S. Route 62 in New York|US&nbsp;62]] at [[Canada–United States border]] on [[Rainbow Bridge (Niagara Falls)|Rainbow Bridge]] in [[Niagara Falls, Ontario|Niagara Falls]]
|established     = 1941-11-01
|established_ref = {{sfnp|Stamp|1987|pp=124–127|ps=.}}
|notes           = none
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 427
|local           = 
|length_km       = 27
|terminus_a      = {{jcon|Hwy|QEW|nosh=y}}/[[Gardiner Expressway]] in [[Toronto]]
|terminus_b      = {{jcon|York|25|nosh=y}} (Major Mackenzie Drive) in [[Vaughan]]
|established     = 1971-12-04
|established_ref = <ref name="assumed427">{{cite news |title = Highway 27 Interchange Fully in Service |work = The Globe and Mail |location = Toronto |date = December 4, 1971 |page = 5 }}</ref>
|notes           = 6.6 km (4.1 mi) extension to Regional Road 25 (Major Mackenzie Drive) opened September 18, 2021
}}
{{routelist row|local
|state           = ON
|type            = Hwy
|route           = 451
|local           = 
|length_km       = 139.1
|terminus_a      = [[Interstate 190 (New York)|I-190]] at [[Canada–United States border]] on [[Peace Bridge]] in [[Fort Erie, Ontario|Fort Erie]]
|terminus_b      = {{jcon|Hwy|427|nosh=y}}/[[Gardiner Expressway]] in [[Toronto]]
|established     = 1937-12-31
|established_ref = {{sfnp|Shragge|Bagnato|1984|pp=79–81|ps=.}}
|notes           = Internally referred to as Highway 451 in the [[Ontario Ministry of Transportation]]
}}
{{routelist bottom|<!-- keys=unbuilt -->}}
{{clear}}

== Gallery ==
<gallery>
File:Highway 401.png|Highway&nbsp;401 south of Pearson Airport is the widest freeway in Canada, and one of the widest and busiest in the world
File:Highway 410 Start.jpg|Aerial view of the interchange between Highway&nbsp;401, 403 and 410 in Mississauga
File:416 into Ottawa.png|An aerial view of Highway&nbsp;416 approaching Ottawa
File:409-427 Interchange.jpg|A sprawling interchange between Highway&nbsp;409 and 427 in Etobicoke, one of several in the Greater Toronto Area
File:Derry and 407.jpg|The [[Parclo A4|Parclo]] interchange design is used throughout the 400-series network
</gallery>

== See also ==
* [[List of provincial highways in Ontario]]
* [[100-series highways (Nova Scotia)|100-Series Highways of Nova Scotia]]
* [[400-series highways (British Columbia)|400-series Highways of British Columbia]]
* [[Autoroute (Quebec)|Quebec Autoroutes]]

== References ==

=== Sources ===
{{Reflist|colwidth=30em}}

=== Bibliography ===
{{refbegin}}
* {{cite book |title = From Footpaths to Freeways |last1 = Shragge |first1 = John |last2 = Bagnato |first2 = Sharon |publisher = Ontario Ministry of Transportation and Communications, Historical Committee |year = 1984 |isbn = 0-7743-9388-2 }}
* {{cite book |title = QEW: Canada's First Superhighway |last = Stamp |first = Robert M. |publisher = The Boston Mills Press |year = 1987 |isbn = 0-919783-84-8 }}
* {{cite book |title = Bridging the Border: Structures of Canadian–American Relations |first = Robert M. |last = Stamp |publisher = Dundurn Press |year = 1992 |location = Toronto |isbn = 1-55002-074-9 }}
* {{cite book
 | title     = '401' The Macdonald–Cartier Freeway
 | publisher = Ministry of Transportation and Communications
 | location  = Toronto
 | year      = 1972
 | ref= {{harvid| Ministry of Transportation and Communications|1972}} }}
* {{cite book
 | ref= {{harvid|Ontario Department of Highways|1970}}
 | title     = AADT Traffic Volumes 1955–1969 and Traffic Collision Data 1967–1969
 | publisher = Ontario Department of Highways
 | year      = 1970}}
{{refend}}

== External links ==
{{Commons category}}
* [http://www.mto.gov.on.ca Ontario Ministry of Transportation] {{Webarchive|url=https://web.archive.org/web/20080511190412/http://www.mto.gov.on.ca/ |date=May 11, 2008 }}
* [http://www.mto.gov.on.ca/english/highway-bridges/southern-and-northern-highways-programs.shtml Highway Construction Programs] {{Webarchive|url=https://web.archive.org/web/20151219193714/http://www.mto.gov.on.ca/english/highway-bridges/southern-and-northern-highways-programs.shtml |date=December 19, 2015 }}
* [https://web.archive.org/web/20141019005901/http://www.asphaltplanet.ca/ON/ Photographs and history on the 400-Series Highways (and other provincial highways, too)]
* ''[https://www.youtube.com/watch?v=lY5fg0RACd8&t Dirt Roads to Freeways ... And All That] {{Webarchive|url=https://web.archive.org/web/20230625053627/https://www.youtube.com/watch?v=lY5fg0RACd8&t |date=June 25, 2023 }}'', ca. 1978, Archives of Ontario YouTube Channel

{{Ontario Controlled Access Highways}}

[[Category:400-series highways| ]]
[[Category:Lists of roads in Ontario|Ontario]]