View source for Arroyo Seco Parkway

{{Short description|Highway in California}}
{{Redirect|Pasadena Freeway|the freeway in Texas|Texas State Highway 225}}
{{Use American English|date=January 2025}}
{{Good article}}
{{Use mdy dates|date=July 2020}}
{{Infobox road|header_type=
|state          = CA
|county         = Los Angeles
|type           = SR
|route          = 110
|name           = Arroyo Seco Parkway
|map            = {{Maplink-road|raw={{Wikipedia:Map data/Wikipedia KML/Arroyo Seco Parkway}}}}
|map_custom     = yes
|map_notes      = Arroyo Seco Parkway highlighted in red
|alternate_name = Pasadena Freeway
|length_mi      = 8.162
|length_ref     = <ref name=trucklist>{{cite web |author = California Department of Transportation |title = State Truck Route List |url = http://www.dot.ca.gov/hq/traffops/trucks/truckmap/truck-route-list.xlsx |location = Sacramento |publisher = California Department of Transportation |archive-url = https://web.archive.org/web/20150905083346/http://www.dot.ca.gov/hq/traffops/trucks/truckmap/truck-route-list.xlsx |archive-date = September 5, 2015 |access-date = June 30, 2015 |url-status = live }}</ref>
|length_round   = 3
|tourist        = [[File:MUTCD D6-4.svg|20px|alt=|link=]][[File:California Scenic State.svg|20px|alt=|link=]] Arroyo Seco Parkway Scenic Byway
|history        = Opened in 1940; renamed in 1954; name reverted in 2010
|restrictions   = No trucks over 3 tons (including buses, unless authorized by the California Public Utilities Commission)<ref name="truckhistory">{{cite web |author = Legal Truck Size & Weight Work Group |date = March 2, 2011 |url = http://www.dot.ca.gov/hq/traffops/trucks/routes/restrict-hist-110.htm |title = Special Route Restriction History: Route 110 |location = Sacramento |publisher = [[California Department of Transportation]] |access-date = May 28, 2015 }}</ref>
|direction_a    = South
|terminus_a     = {{jct|state=CA|US|101|SR|110}} in [[Los Angeles]]
|junction       = {{jct|state=CA|I|5}} in Los Angeles
|direction_b    = North
|terminus_b     = Glenarm Street in [[Pasadena, California|Pasadena]]
|system1        = '''[[Southern California freeways]]'''
|embedded       = {{Infobox NRHP|embed=yes
 | name           = Arroyo Seco Parkway Historic District
 | nrhp_type      = hd
 | nocat          = yes 
 | added          = February 17, 2011
 | governing_body =
 | refnum         = 10001198<ref name="nris">{{cite web |author = National Park Service |author-link = National Park Service |url = https://www.nps.gov/subjects/nationalregister/upload/weekly-list-2011-national-register-of-historic-places.pdf |title = National Register of Historic Places Weekly Action List |date = February 4, 2011 |work = National Register of Historic Places |publisher = National Park Service |access-date = July 27, 2012 }}</ref>
 }}
}}

The '''Arroyo Seco Parkway''', also known as the '''Pasadena Freeway''', is one of the oldest [[controlled-access highway|freeways]] in the [[United States]]. It connects [[Los Angeles, California|Los Angeles]] with [[Pasadena, California|Pasadena]] alongside the [[Arroyo Seco (Los Angeles County)|Arroyo Seco]] seasonal river. Mostly opened in 1940, it represents the transitional phase between early parkways and later freeways. It conformed to modern standards when it was built, but is now regarded as a narrow, outdated roadway.<ref>*{{cite book |publisher = [[Historic American Engineering Record]] |first1 = J. Philip |last1 = Gruen |first2 = Portia |last2 = Lee |name-list-style=amp|url = http://www.arroyoseco.org/HAERASP.pdf |title = Arroyo Seco Parkway (HAER No. CA-265) |date = August 1999 |access-date = July 29, 2011 |pages = 4–5 }}</ref> A 1953 extension brought the south end to the [[Four Level Interchange]] in [[downtown Los Angeles]] and a connection with the rest of the freeway system.

The road remains largely as it was on opening day, though the plants in its [[median (road)|median]] have given way to a steel [[guard rail]], and most recently to [[Constant-slope barrier|concrete barriers]], and it now carries the designation [[State Route 110 (California)|State Route 110]], not historic [[U.S. Route 66 (California)|U.S. Route 66]]. Between 1954 and 2010, it was designated the Pasadena Freeway. In 2010, as part of plans to revitalize its scenic value and improve safety, the [[California Department of Transportation]] (Caltrans) restored the roadway's original name.<ref>{{cite news |last = Pool |first = Bob |title = Pasadena Freeway Getting a New Look and a New Name |work = [[Los Angeles Times]] |date = June 25, 2010 |url = https://www.latimes.com/archives/la-xpm-2010-jun-25-la-me-parkway-20100625-story.html |access-date = July 29, 2011 }}</ref> All of its original bridges remain, including four that predate the parkway itself, built across the Arroyo Seco before the 1930s. The road has a crash rate roughly twice the rate of other freeways, largely due to an outdated design lacking in acceleration and deceleration lanes.<ref name=FHWA />

The Arroyo Seco Parkway is designated a [[State Scenic Highway (California)|State Scenic Highway]], [[National Historic Civil Engineering Landmark]], and [[National Scenic Byway]]. It was listed in the [[National Register of Historic Places]] in 2011.

== Route description ==
[[File:SR 110 north over LA River.jpg|thumb|left|Northbound over the [[Los Angeles River]]]]
The six-lane Arroyo Seco Parkway (part of [[State Route 110 (California)|State Route 110]]) begins at the [[Four Level Interchange]], a symmetrical [[stack interchange]] on the north side of [[downtown Los Angeles]] that connects the Pasadena (SR 110 north), [[Harbor Freeway|Harbor]] (SR 110 south), Hollywood ([[US 101 (CA)|US 101]] north), and [[Santa Ana Freeway|Santa Ana]] (US 101 south) Freeways. The first interchange is with the north end of [[Figueroa Street]] at Alpine Street, and the freeway then meets the north end of [[Hill Street (Los Angeles)|Hill Street]] at a complicated junction that provides access to [[Dodger Stadium]]. Beyond Hill Street, SR 110 temporarily widens to four northbound and five southbound lanes as it enters the hilly [[Elysian Park, Los Angeles, California|Elysian Park]], where the northbound lanes pass through the four [[Figueroa Street Tunnels]] and the higher southbound lanes pass through a [[cut (terrain)|cut]] and over low areas on bridges. One interchange, with Solano Avenue and Amador Street, is located between the first and second tunnels. Just beyond the last tunnel is a northbound left exit and corresponding southbound right entrance for [[Riverside Drive (Los Angeles)|Riverside Drive]] and the northbound [[Golden State Freeway]] ([[I-5 (CA)|I-5]]). Immediately after those ramps, the Arroyo Seco Parkway crosses a pair of three-lane bridges over the [[Los Angeles River]] just northwest of its confluence with the [[Arroyo Seco (Los Angeles)|Arroyo Seco]], one [[rail line]] on each bank, and Avenue 19 and [[San Fernando Road]] on the north bank. A single onramp from San Fernando Road joins SR 110 northbound as it passes under I-5, and a northbound left exit and southbound right entrance connect to the north segment of [[Figueroa Street]]. Here the original 1940 freeway, mostly built along the west bank of the Arroyo Seco, begins as the southbound lanes curve from their 1943 alignment over the Los Angeles River into the original alignment next to the northbound lanes.<ref name=maps>{{cite map |author1 = ((Google)) |author-link = Google |author2 = ((United States Geological Survey)) |author2-link = United States Geological Survey |name-list-style=amp|title = Street Maps and Topographic Maps |access-date = January 15, 2008 |url = http://mapper.acme.com/ |publisher = ACME Mapper |archive-url = https://web.archive.org/web/20080102075829/http://mapper.acme.com/ |archive-date = January 2, 2008 |url-status = live }}</ref>

[[File:Arroyo Seco Parkway under Avenue 26.jpg|thumb|Avenue 26 Bridge]]
As the original freeway begins, it passes under an extension to the 1925 Avenue 26 Bridge, one of four bridges over the Arroyo Seco that predate the parkway's construction. A southbound exit and northbound entrance at Avenue 26 complement the Figueroa Street ramps, and similar ramps connect Pasadena to both directions of I-5. SR 110 continues northeast alongside the Arroyo Seco, passing under the [[A Line (Los Angeles Metro)|A Line]] [[light rail]] and Pasadena Avenue before junctioning Avenue 43 at the first of many [[folded diamond interchange]]s that feature extremely tight ([[right-in/right-out]]) curves on the exit and entrance ramps. The next interchange, at Avenue 52, is a normal [[diamond interchange]], and soon after is Via Marisol, where the northbound side has standard diamond ramps, but on the southbound side Avenue 57 acts as a folded diamond connection. The 1926 [[Avenue 60 Bridge]] is the second original bridge, and is another folded diamond, with southbound traffic using Shults and Benner Streets to connect. The 1895 [[Santa Fe Arroyo Seco Railroad Bridge]] (now [[A Line (Los Angeles Metro)|A Line]]) lies just beyond, and after that is a [[half diamond interchange]] at Marmion Way/Avenue 64 with access towards Los Angeles only. After the freeway passes under the 1912 [[York Boulevard Bridge]], the pre-parkway bridge, southbound connections between the freeway and cross street can be made via Salonica Street. As the Arroyo Seco curves north to pass west of downtown Pasadena, the Arroyo Seco Parkway instead curves east, crossing the stream into [[South Pasadena, CA|South Pasadena]]. A single northbound offramp on the Los Angeles side of the bridge curves left under the bridge to Bridewell Street, the parkway's west-side [[frontage road]].<ref name=maps/>

[[File:Arroyo Seco Parkway from Marmion Way.jpg|thumb|left|Looking south from Marmion Way showing the passing lanes, differently-colored from using different paving materials.]]
As they enter South Pasadena, northbound motorists can see a "City of South Pasadena" sign constructed, in the late 1930s, of stones from the creek bed embedded in a hillside.<ref>{{harvp|Gruen|Lee|1999|pp=9, 51}}.</ref> This final segment of the Arroyo Seco Parkway heads east in a cut alongside Grevelia Street, with a full diamond at Orange Grove Avenue and a half diamond at [[Fair Oaks Avenue]]. In between those two streets it crosses under the A Line for the third and final time. Beyond Fair Oaks Avenue, SR 110 curves north around the east side of [[Raymond Hill (California)|Raymond Hill]] and enters Pasadena, where the final ramp, a southbound exit, connects to State Street for access to Fair Oaks Avenue. The freeway, and state maintenance,<ref name=trucklist/> ends at the intersection with Glenarm Street, but the six- and four-lane Arroyo Parkway, now maintained by the city of Pasadena, continues north as a surface road to [[Colorado Boulevard]] (historic [[U.S. Route 66 in California|U.S. Route&nbsp;66]]) and beyond to Holly Street near the [[Memorial Park station|Memorial Park]] A Line station.<ref name=maps/>

== Route usage ==

According to Caltrans in 2016, the average annual daily traffic (AADT) on the Arroyo Seco Parkway was 78,000 car trips at Orange Grove Blvd, 100,000 car trips at Ave 64, and 123,000 car trips at Ave 43.

== History ==

=== Planning ===
[[File:WelcomeToTheHistoricArryoSecoParkway.jpg|thumb|Sign welcoming drivers to the parkway|alt=Photograph]]

The [[Arroyo Seco (Los Angeles County)|Arroyo Seco]] ([[Spanish (language)|Spanish]]: "dry creek, dry gulch, or streambed") is an [[intermittent stream]] that carries rainfall from the [[San Gabriel Mountains]] southerly through western Pasadena into the [[Los Angeles River]] near [[downtown Los Angeles]]. During the dry season, it served as a faster [[wagon]] connection between the two cities than the all-weather road on the present Huntington Drive.<ref>{{harvp|Gruen|Lee|1999|pp=9–10}}.</ref>

The first known survey for a permanent roadway through the Arroyo was made by T. D. Allen of Pasadena in 1895, and in 1897 two more proposals were made, one for a scenic [[parkway]] and the other for a [[commuter]] [[cycleway]]. The latter was partially constructed and opened by [[Horace Dobbins]], who incorporated the [[California Cycleway]] Company and bought a six-mile (10&nbsp;km) [[Right-of-way (transportation)|right-of-way]] from downtown Pasadena to Avenue 54 in [[Highland Park, Los Angeles, California|Highland Park, Los Angeles]]. Construction began in 1899, and about {{convert|1+1/4|mi|km}} of the elevated wooden bikeway were opened on January 1, 1900, starting near Pasadena's [[Hotel Green]] and ending near the [[Raymond Hotel (Pasadena)|Raymond Hotel]]. The majority of its route is now Edmondson Alley; a [[Toll house|toll booth]] was located near the north end, in the present [[Central Park (Pasadena)|Central Park]]. Due to the end of the [[bicycle craze]] of the 1890s and the existing [[Pacific Electric Railway]] lines connecting Pasadena to Los Angeles, the cycleway did not and was not expected to turn a profit, and never extended beyond the Raymond Hotel into the Arroyo Seco. Sometime before 1910, the structure was dismantled, and the wood sold for [[lumber]],<ref>{{cite book |first = Ann |last = Scheid |title = Downtown Pasadena's Early Architecture |location = Charleston, South Carolina |publisher = [[Arcadia Publishing]] |series = Images of America |year = 2006 |pages = 78–79 |isbn = 978-0-7385-3024-6 }}</ref><ref name=sopa>{{cite book |first = Rick R. |last = Thomas |title = South Pasadena |location = Charleston, South Carolina |publisher = Arcadia Publishing |series = Images of America |year = 2007 |pages = 60–65 |isbn = 978-0-7385-4748-0 }}</ref> and the Pasadena Rapid Transit Company, a failed venture headed by Dobbins to construct a [[streetcar line]], acquired the right-of-way.<ref>{{cite news |work = Los Angeles Times |title = Dash into Pasadena in Twelve Minutes |date = January 1, 1909 |page = II1 }}</ref><ref>{{harvp|Gruen|Lee|1999|pp=17–18, 23}}.</ref>

[[File:California Cycleway 1900.jpg|thumb|left|The [[California Cycleway]], 1900]]

Due to the rise of the automobile, most subsequent plans for the Arroyo Seco included a roadway, though they differed as to the purpose: some, influenced by the [[City Beautiful movement]], concentrated on the park, while others, particularly those backed by the [[Automobile Club of Southern California]] (ACSC), had as their primary purpose a fast road connecting the two cities. The first plan that left the Arroyo Seco in [[South Pasadena, CA|South Pasadena]] to better serve downtown Pasadena was drawn up by Pasadena City Engineer Harvey W. Hincks in 1916 and supported by the Pasadena Chamber of Commerce and ACSC. [[Frederick Law Olmsted Jr.]] and [[Harland Bartholomew]]'s 1924 ''Major Street Traffic Plan for Los Angeles'', while concentrating on traffic relief, and noting that the Arroyo Seco Parkway would be a major highway, suggested that it be built as a [[parkway]], giving motorists "a great deal of incidental recreation and pleasure". By the mid-1930s, plans for a primarily recreational parkway had been overshadowed by the need to carry large numbers of commuters.<ref>{{harvp|Gruen|Lee|1999|pp=18–26}}.</ref>

Debates continued on the exact location of the parkway, in particular whether it would bypass downtown Pasadena. In the late 1920s, Los Angeles acquired properties between [[San Fernando Road]] and Pasadena Avenue, and City Engineer Lloyd Aldrich began grading between Avenues 60 and 66 in the early 1930s. By June 1932, residents of [[Highland Park, CA|Highland Park]] and [[Garvanza, CA|Garvanza]], who had paid [[special assessment]]s to finance improvement of the park, became suspicious of what appeared to be a road, then graded along the Arroyo Seco's west side between Via Marisol (then Hermon Avenue) and Princess Drive. Merchants on North Figueroa Street (then Pasadena Avenue) also objected, due to the loss of business they would suffer from a bypass. Work stopped while the interested parties could work out the details, although, in late 1932 and early 1933, Aldrich was authorized to grade a cheaper route along the east side between Avenue 35 and Hermon Avenue. To the north, Pasadena and South Pasadena endorsed in 1934 what was essentially Hincks's 1916 plan, but lacked the money to build it. A bill was introduced in 1935 to add the route to the state highway system, and after some debate a new '''Route 205''' was created as a swap for the [[Palmdale, CA|Palmdale]]-[[Wrightwood, CA|Wrightwood]] [[Legislative Route 186 (California 1933-1935)|Route 186]],<ref>{{cite CAstat |year = 1935 |ch = 426 |p = 288, 1480 }} "A new route or portion of route is hereby added to the State highway system from Route&nbsp;165 [Figueroa Street] near Los Angeles River in Los Angeles to Route&nbsp;161 [Colorado Boulevard] in Pasadena at Broadway Avenue."</ref><ref>{{cite CAstat |year = 1937 |ch = 841 |p = 2361 }} "Route&nbsp;205 is from Route&nbsp;165 near Los Angeles River in Los Angeles to Route&nbsp;161 in Pasadena at Broadway Avenue."</ref> as the legislature had just greatly expanded the system in 1933, and the [[California Highway Commission]] opposed a further increase.<ref>{{harvp|Gruen|Lee|1999|pp=29–34}}.</ref>

=== Construction ===
{{Further|Figueroa Street Tunnels}}
[[File:FigueroaStTunnels.jpg|thumb|The [[Figueroa Street Tunnels]]]]
To connect the proposed parkway with downtown Los Angeles, that city improved and extended North [[Figueroa Street]] as a four-lane road to the [[Los Angeles River]], allowing drivers to bypass the congested [[North Broadway Bridge]] on the existing but underutilized [[Riverside Drive Bridge]]. A large part of the project lay within [[Elysian Park, Los Angeles, California|Elysian Park]], and four [[Art Deco]] [[tunnel]]s were built through the hills. The first three, between Solano Avenue and the river, opened in late 1931,<ref>{{cite news |work = Los Angeles Times |title = By-pass Route Through Elysian Park Tunnels Opened to Automobile Traffic |date = November 1, 1931 |page = E1 }}</ref> and the fourth opened in mid-1936,<ref>{{cite news |work = Los Angeles Times |title = Shaw Opens New Tunnel |date = August 5, 1936 |page = A1 }}</ref> completing the extension of Figueroa Street to [[Riverside Drive (Los Angeles)|Riverside Drive]]. As with the contemporary [[Ramona Boulevard]] east from downtown, [[grade separation]]s were mostly built only where terrain dictated. For Figueroa Street, this meant that all crossings except College Street (built several years after the extension was completed<ref>{{cite news |work = Los Angeles Times |title = Street Job Bids Will Be Opened |date = August 15, 1938 |page = A10 }}</ref>), where a hill was cut through, were [[at-grade intersection|at grade]].<ref>{{cite AV media |url = http://digarc.usc.edu/search/controller/view/chs-m2270.html |title = Aerial view of Chavez Ravine in Los Angeles, looking west, ca. 1940 |date = 1940 |location = Los Angeles |publisher = [[University of Southern California]] Libraries Digital Archive |people = Prejza, Paul (donor) |id = chs-m2270 |medium = Photograph |access-date = January 14, 2008 |archive-date = January 23, 2008 |archive-url = https://web.archive.org/web/20080123174354/http://digarc.usc.edu/search/controller/view/chs-m2270.html |url-status = dead }}</ref> The [[Figueroa Street Viaduct]], connecting the Riverside Drive intersection with North Figueroa Street (then Dayton Avenue) across the [[Los Angeles River]], opened in mid-1937.<ref>{{cite news |work = Los Angeles Times |title = New Bridge Dedicated |date = July 7, 1937 |page = A2 }}</ref> Closer to downtown, an [[interchange (road)|interchange]] was built at [[Temple Street (Los Angeles)|Temple Street]] in 1939.<ref>{{cite news |work = Los Angeles Times |title = Traffic Project Work Pushed |date = May 11, 1939 |page = A1 }}</ref><ref>{{harvp|Gruen|Lee|1999|pp=27–28, 53–54}}.</ref>

[[File:North Figueroa Bridge 1938.jpg|left|upright|thumb|The [[Figueroa Street Viaduct]], 1938 (Riverside Drive is to the left, and its bridge is in the left background)]]
Although many South Pasadena residents opposed the division of the city that the parkway would bring, the city's voters elected supporters in the 1936 elections. The state, which had the power to put the road where it wished even had South Pasadena continued to oppose it, approved the route on April 4, 1936. The route used the Arroyo Seco's west bank to near Hough Street, where it crossed to the east and cut through South Pasadena to the south end of Broadway (now Arroyo Parkway) in Pasadena. Another project, the [[Arroyo Seco Flood Control Channel]], was built by the [[Works Progress Administration]] before and during construction of the parkway to avoid damages from future floods. A number of state engineers toured [[East Coast of the United States|East Coast]] roads in early 1938, including [[Chicago, IL|Chicago]]'s [[Lake Shore Drive]], full and modified [[cloverleaf interchange]]s in [[Massachusetts]] and [[New Jersey]], and [[Robert Moses]]'s parkway system in [[New York City]]. The parkway was the first road built in California under a 1939 [[freeway]] law that allowed access to be completely limited to a number of specified points. Although, in some areas, it was possible to use a standard [[diamond interchange]], other locations required [[folded diamond]]s, or, as the engineers called them, "compressed cloverleafs", where local streets often took the place of dedicated ramps, ending at the parkway with a sharp right turn required to enter or exit. The highway was designed with two {{convert|11|–|12|ft|m|adj=on}} lanes and one {{convert|10|ft|m|adj=on}} [[shoulder (road)|shoulder]] in each direction, with the wider inside (passing) lanes paved in black [[asphalt concrete]] and the outside lanes paved in white [[Portland cement concrete]]. The differently-colored lanes would encourage drivers to stay in their lanes. (By mid-1939, the state had decided to replace the shoulders with additional travel lanes for increased capacity; except on a short piece in South Pasadena, these were also paved with Portland cement. So that [[disabled vehicle]]s could be safely removed from the roadway, about 50 "safety bays" were constructed in 1949 and 1950.<ref>{{harvp|Gruen|Lee|1999|pp=60, 69}}.</ref>) The engineers used a [[design speed]] of {{convert|45|mph|km/h|abbr=off}}, [[Cant (road/rail)|superelevating]] curves where necessary to accomplish this. (The road is now posted at {{convert|55|mph|km/h|abbr=on}}.<ref>{{harvp|Gruen|Lee|1999|p=68}}.</ref>) Despite the freeway design, many parkway characteristics were incorporated, such as plantings of mostly native flora alongside the road.<ref>{{harvp|Gruen|Lee|1999|pp=34–51}}.</ref>

Prior to parkway construction, nine roads and two [[rail line]]s crossed the Arroyo Seco and its valley on bridges, and a number of new bridges were built as part of the project. Only four of the existing bridges were kept, albeit with some changes:<ref name=bridgelog>{{Caltrans bridgelog |date = July 2015 }}</ref><ref name=traffic>{{cite web |author = Traffic and Vehicle Data Systems Unit |publisher = California Department of Transportation |url = http://traffic-counts.dot.ca.gov/2006all.htm |title = All Traffic Volumes on CSHS |year = 2006 |access-date = July 29, 2011 |archive-url = https://web.archive.org/web/20110721033203/http://traffic-counts.dot.ca.gov/2006all.htm |archive-date = July 21, 2011 |url-status = dead }}</ref><ref name=NBI>[[National Bridge Inventory]] database, 2006{{full citation needed|date=July 2015}}</ref><!--because the Avenue 60 Bridge is only original over the arroyo--> the 1925 [[Avenue 26 Bridge]], the 1926<!--why does NBI say 1909??--> [[Avenue 60 Bridge]], the 1895<!--exactly? some sources say circa--> [[Santa Fe Arroyo Seco Railroad Bridge]] (now part of the [[A Line (Los Angeles Metro)]]) near Avenue 64, and the 1912<!--not 1911 - see Los Angeles Times, Bridge Nearly Completed, January 15, 1912--> [[York Boulevard Bridge]]. The Avenue 43 Bridge would have been kept had the [[Los Angeles Flood of 1938]] not destroyed it. At Cypress Avenue, [[abutment]]s and a [[foundation (construction)|foundation]] were built for a roadway, but were not used until the 1960s, when a pedestrian bridge was built as part of the [[Golden State Freeway]] ([[I-5 (CA)|I-5]]) interchange project.<ref name=bridgelog/> In South Pasadena, seven streets and the Union Pacific and Santa Fe railroad lines on a double track combined bridge were carried over the parkway to keep the communities on each side connected.<ref>{{harvp|Gruen|Lee|1999|pp=51–55}}.</ref>

[[File:ArroyoSecoPkwy(CA110)1940.jpg|thumb|The Marmion Way (foreground) and York Boulevard (background) bridges in 1940]]
Construction on the Arroyo Seco Parkway, designed under the leadership of District Chief Engineer Spencer V. Cortelyou and Design Engineer A. D. Griffin, began with a [[groundbreaking ceremony]] in South Pasadena on March 22, 1938, and generally progressed from Pasadena southwest. The first contract, stretching less than a mile (1.5&nbsp;km) from Glenarm Street in Pasadena around Raymond Hill to [[Fair Oaks Avenue]] in South Pasadena, and including no bridges, was opened to traffic on December 10, 1938. A 3.7-mile (6.0&nbsp;km) section opened on July 20, 1940, connecting Orange Grove Avenue in South Pasadena with Avenue 40 in Los Angeles.<ref>{{cite news |work = Los Angeles Times |title = New Highway Opens Saturday |date = July 17, 1940 |page = A12 }}</ref> The remainder in Los Angeles, from Avenue 40 southwest to the Figueroa Street Viaduct at Avenue 22, was dedicated on December 30, 1940, with great fanfare, and opened to the public the following day in time for the [[Tournament of Roses Parade]] and [[Rose Bowl (game)|Rose Bowl]] on [[New Year's Day]].<ref>{{Cite web |date = April 11, 2016 |title = History of the Arroyo Seco Parkway Preserved in Museum's Archives |url = https://pasadenahistory.org/collections/arroyo-parkway/ |access-date = July 18, 2020 |publisher = Pasadena Museum of History }}</ref> However, the highway through South Pasadena was not completed until January 30, 1941, and landscaping work continued through September. The final cost of $5.75 million, under $1 million per mile, was extremely low for a freeway project because the terrain was favorable for grade separations.<ref>{{harvp|Gruen|Lee|1999|pp=55–59}}.</ref>

[[File:Arroyo Seco Parkway through Elysian Park.jpg|thumb|left|Through [[Elysian Park, Los Angeles, California|Elysian Park]]: [[Figueroa Street Tunnels]] at left, 1943 lanes at right]]
The state began upgrading the four-lane North Figueroa Street extension (then part of [[Legislative Route 165 (California pre-1964)|Route 165]]) in October 1940 as a "Southerly Extension" of the parkway, even before the parkway was complete. The at-grade intersection with Riverside Drive was already a point of congestion, and the six lanes of parkway narrowing into four lanes of surface street would cause much greater problems. The two-way Figueroa Street Tunnels and Viaduct were repurposed for four lanes of northbound traffic, and a higher southbound roadway was built to the west. From the split with [[Hill Street (Los Angeles)|Hill Street]] south to near the existing College Street overpass, the four-lane surface road became a six-lane freeway. The extension was designed almost entirely on freeway, rather than parkway, principles, as it had to be built quickly to handle existing traffic. The new road split from the old at the Figueroa Street interchange, just south of Avenue 26, and crossed the [[Los Angeles River]] and the northbound access to Riverside Drive on a new three-lane bridge. Through Elysian Park, a five-lane open cut was excavated west of the existing northbound tunnel lanes, saving about $1 million. The extension, still feeding into surface streets just south of College Street, was opened to traffic on December 30, 1943, again allowing its use for the New Year's Day festivities.<ref>{{harvp|Gruen|Lee|1999|pp=59–64}}.</ref>

[[File:Four Level Interchange.jpg|thumb|The [[Four Level Interchange]], looking northeast along the Pasadena Freeway; the interchange at Figueroa and Temple Streets is in the right foreground]]
While the Arroyo Seco Parkway was being built and extended, the region's freeway system was taking shape. The short city-built [[Cahuenga Pass Freeway]] opened on June 15, 1940,<ref>{{cite web |author = City of Los Angeles |date = December 22, 2005 |url = http://www.lacity.org/LADOT/TopicsAndTales/Freeway4.pdf |title = Cahuenga Parkway |work = Transportation Topics & Tales |publisher = City of Los Angeles |archive-url = https://web.archive.org/web/20080228095516/http://www.lacity.org/LADOT/TopicsAndTales/Freeway4.pdf |archive-date = February 28, 2008 |access-date = January 14, 2008 }}</ref> over a month before the second piece of the Arroyo Seco Parkway was complete. In the next two decades, the [[Harbor Freeway|Harbor]], [[U.S. Route 101 in California|Hollywood]] (Cahuenga Pass), [[Long Beach Freeway|Long Beach]] (Los Angeles River), [[San Bernardino Freeway|San Bernardino]] (Ramona), and [[Santa Ana Freeway|Santa Ana]] Freeways were partially or fully completed to their [[eponym]]ous destinations, and others were under construction.<ref>{{cite map |author = Rand McNally |author-link = Rand McNally |url = http://cahighways.org/maps/1959rmn.jpg |title = Los Angeles and Vicinity |year = 1959 |location = Chicago |publisher = Rand McNally |access-date = July 29, 2011 |archive-url = https://web.archive.org/web/20110725122839/http://cahighways.org/maps/1959rmn.jpg |archive-date = July 25, 2011 |url-status = live }}</ref> The centerpiece of the system was the [[Four Level Interchange]] just north of [[downtown Los Angeles]], the first [[stack interchange]] in the world. Although it was completed in 1949, the structure was not fully used until September 22, 1953, when the short extension of the Arroyo Seco Parkway to the interchange opened. Though the common name used by the public had become "Arroyo Seco ''Freeway''" over the years, it was officially a "Parkway" until November 16, 1954, when the [[California Highway Commission]] changed its name to the '''Pasadena Freeway'''.<ref>{{harvp|Gruen|Lee|1999|pp=64–67}}.</ref>

Beginning in June 2010, the state began modifying interchange signs to remove the Pasadena Freeway name and reinstate the Arroyo Seco Parkway name. Signs that indicate route 110 as a "freeway" are being modified to "parkway" or its "Pkwy" abbreviation.

=== Post-construction ===
[[File:I-5 SR 110 interchange from Elysian Park.jpg|thumb|upright|left|[[Golden State Freeway]] interchange, looking northeast]]
Despite a quadrupling of traffic volumes, the original roadway north of the Los Angeles River largely remains as it was when it opened in 1940. [[Truck]]s and [[bus]]es were banned in 1943, though the bus restriction has since been dropped; this has kept the freeway in good condition. Except for the [[Golden State Freeway]] ([[I-5 (CA)|I-5]]) interchange near the river, completed in 1962, the few structural changes to the freeway north of the river include the closure of the original southbound exit to Fair Oaks Avenue after its location on a curve proved dangerous<ref name=sopa /> and the replacement of shrubs in the {{convert|4|ft|m|adj=on}} [[median (road)|median]] with a steel and now concrete [[guard rail]].<!--not mentioning the 1951 pedestrian bridge because it's not over the freeway--> Los Angeles paid for reconstruction of the interchange at Hill Street, south of Elysian Park, in the early 1960s to serve the new [[Dodger Stadium]].<ref>{{harvp|Gruen|Lee|1999|pp=67–72}}.</ref>  An interchange with Amador Street once had both left and right exits and entrances, it now only has a right exit and entrance.

The parkway's design is now outdated, and includes tight "[[right-in/right-out]]" access with a recommended exit speed of {{convert|5|mph|km/h}} and [[stop sign]]s on the entrance ramps.{{cn|date=April 2024}} There are no [[acceleration or deceleration lane]]s, meaning that motorists must attempt to merge immediately into freeway traffic from a complete stop.<ref name=WashingtonLAist>{{cite news |last1=Washington |first1=Aaricka |title=Yes, Merging Onto The 110's Arroyo Seco Parkway Is Terrifying. We Have Pictures And Stories |url=https://laist.com/news/how-to-la/110-freeway-merging-fear-horror-los-angeles |access-date=April 13, 2024 |work=LAist |date=February 7, 2024 |language=en}}</ref> While the curves are [[Cant (road/rail)|banked]] for higher speeds, they were designed at half the modern standard. A three-year [[Caltrans]] study determined that the parkway has a crash rate that is twice that of comparable highways, with the primary factor being the lack of acceleration and deceleration lanes.<ref name=FHWA>{{cite book |first1 = William J. |last1 = Stein |first2 = Timothy R. |last2 = Neuman |date= July 2007 |chapter = Case Study 4: State Route 110 (The Arroyo Seco Parkway) |title = Mitigation Strategies For Design Exceptions |url = https://safety.fhwa.dot.gov/geometric/pubs/mitigationstrategies/fhwa_sa_07011.pdf |archive-url = https://web.archive.org/web/20090621045318/http://safety.fhwa.dot.gov/geometric/pubs/mitigationstrategies/fhwa_sa_07011.pdf |url-status = dead |archive-date = June 21, 2009 |type =  Report |publisher = Federal Highway Administration |page = 146 |id = FHWA-SA-07-011 |quote = The California Department of Transportation (Caltrans) conducted a 3-year crash analysis for the corridor. The data indicated a crash rate about twice the average rate for similar highway types. There were 1,217 total crashes over this time period. Of these, 324 crashes involved the median barrier, resulting in 111 injuries and 1 fatality. The analysis also showed concentrations of crashes at entrance and exit ramps and concluded that a primary causal factor is the limited acceleration and deceleration lengths.}}</ref> ''[[LAist]]'' noted that many motorists find the act of merging onto the parkway to be "terrifying".<ref name=WashingtonLAist />

The Arroyo Seco Parkway was the first freeway in the Western United States.<ref name=fisher>{{cite news |url = http://wheels.blogs.nytimes.com/2008/08/15/shabby-road-the-ills-and-charms-of-californias-first-freeway/ |title = Shabby Road: The Ills and Charms of California's First Freeway |work = [[The New York Times]] |date = August 15, 2008 |last = Fisher |first = Jay |access-date = November 16, 2011 }}</ref> It became a new alignment of [[U.S. Route 66 (California)|U.S. Route 66]], and the old routing via [[Figueroa Street]] and [[Colorado Boulevard]] became [[U.S. Route 66 Alternate (Los Angeles, California)|U.S. Route 66 Alternate]].<ref>{{cite web |title = Correspondence between the Division of Highways and American Association of State Highway Officials |url = http://cahighways.org/065-072.html#066 |work = California Highways |first = Daniel P. |last = Faigin |access-date = July 29, 2011 |archive-url = https://web.archive.org/web/20110628195323/http://www.cahighways.org/065-072.html |archive-date = June 28, 2011 |url-status = live }}</ref> The southern extension over the Los Angeles River to downtown Los Angeles also carried [[California State Route 11 (1934)|State Route 11]] (which remained on the old route when US 66 was moved) and U.S. Routes [[US 6 (CA)|6]] and [[US 99 (CA)|99]] (which followed Avenue 26 and [[San Fernando Road]] to the northwest).<ref>{{cite map |author = California Division of Highways |url = http://www.americanroads.us/citymaps/1944CaStateMapLosAngeles.png |title = Los Angeles and Vicinity |year = 1944 |location = Sacramento |publisher = California Division of Highways |access-date = July 29, 2011 |archive-url = https://web.archive.org/web/20110722012402/http://www.americanroads.us/citymaps/1944CaStateMapLosAngeles.png |archive-date = July 22, 2011 |url-status = live |via = American Roads }}</ref> The [[1964 renumbering (California)|1964 renumbering]] saw US 66 truncated to Pasadena, and SR 11 was moved from Figueroa Street (which became [[SR 159 (CA)|SR 159]]) to the Pasadena Freeway.<ref>{{cite magazine |url = https://archive.org/stream/californiahighwa196465calirich#page/n85/mode/2up |title = Route Renumbering: New Green Markers Will Replace Old Shields |magazine = California Highways and Public Works |date = March–April 1964 |volume = 43 |issue = 3–4 |pages = 11–13 |issn = 0008-1159 |via = Archive.org |access-date = March 8, 2012 }}</ref> Finally, the number was changed to [[SR 110 (CA)|SR 110]] in 1981, when SR 11 between [[San Pedro, CA|San Pedro]] and the [[Santa Monica Freeway]] ([[I-10 (CA)|I-10]]) became [[I-110 (CA)|I-110]].<ref>{{cite CAstat |year = 1981 |ch = 292 |p = 1418 }} "Route 110 is from San Pedro to Colorado Boulevard in Pasadena."</ref>

[[File:ArroyoFest.jpg|thumb|ArroyoFest, 2003]]

Despite its flaws, the Arroyo Seco Parkway remains the most direct car route between downtown Los Angeles and Pasadena; the only freeway alternate (which trucks must use) is the [[Glendale Freeway]] ([[SR 2 (CA)|SR 2]]) to the northwest. (LA Metro's [[A Line (Los Angeles Metro)|A Line]] [formerly the [[L Line (Los Angeles Metro)|Gold Line]]] provides light rail service along the former [[Santa Fe Railway]] line.) The state legislature designated the original section of the Parkway, north of the Figueroa Street Viaduct, as a "California Historic Parkway" (part of the [[State Scenic Highway System (California)|State Scenic Highway System]] reserved for freeways built before 1945) in 1993;<ref>{{cite CAstat |year = 1993 |ch = 179 }}</ref> the only other highway so designated is the [[Cabrillo Freeway]] ([[SR 163 (CA)|SR 163]]) in [[San Diego, CA|San Diego]]. The [[American Society of Civil Engineers]] named it a [[National Historic Civil Engineering Landmark]] in 1999,<ref>{{harvp|Gruen|Lee|1999|p=4}}.</ref> and it became a [[National Scenic Byway]] in 2002<ref>{{cite press release |first = Lori |last = Irving |publisher = [[Federal Highway Administration]] |url = https://www.fhwa.dot.gov/pressroom/fhwa0227.cfm |title = U.S. Transportation Secretary Mineta Names 36 New National Scenic Byways, All-American Roads |date = June 13, 2002 |access-date = July 29, 2011 }}</ref> and was added to the [[National Register of Historic Places]] in 2011.<ref name="nris"/> [[Occidental College]] hosted the "ArroyoFest Freeway Walk and Bike Ride" on Sunday, June 15, 2003, closing the freeway to motor vehicles to "highlight several ongoing or proposed projects within the Arroyo that can improve the quality of life for everyone in the area".<ref>{{cite web |url = http://www.arroyofest.org/faq2.htm |publisher = ArroyoFest |title = Frequently Asked Questions |access-date = January 15, 2008 |archive-url = https://web.archive.org/web/20080703200013/http://www.arroyofest.org/faq2.htm |archive-date = July 3, 2008 }}</ref> The event was held again twenty years later, in October 2023.<ref>{{Cite web |date=October 29, 2023 |title=Cyclists took over the 110 Freeway: Here's what they had to say biking in LA |url=https://www.latimes.com/california/story/2023-10-29/arroyo-fest-what-cyclists-think-about-biking-in-la |access-date=October 30, 2023 |website=Los Angeles Times |language=en-US}}</ref> Over 50,000 attended the event.<ref>{{Cite web |date=October 29, 2023 |title=Tens of thousands take to the 110 Freeway for ArroyoFest event |url=https://www.pasadenastarnews.com/2023/10/29/no-cars-on-the-110-freeway-from-pasadena-to-l-a-second-ever-arroyofest-draws-a-crowd/ |access-date=October 30, 2023 |website=Pasadena Star News |language=en-US}}</ref>

== Exit list ==
Mileage is measured from [[Interstate 110 and State Route 110 (California)|Route&nbsp;110]]'s southern terminus in [[San Pedro, Los Angeles|San Pedro]].
{{CAinttop|exit
|county=Los Angeles
|length_ref=<ref name=CalNexus/><ref>{{cite web |author = Traffic and Vehicle Data Systems Unit |publisher = California Department of Transportation |url = http://traffic-counts.dot.ca.gov/2002all.htm |title = All Traffic Volumes on CSHS |year = 2002 }}{{Dead link|date=June 2020 |bot=InternetArchiveBot |fix-attempted=yes }}<!--the last year before the relinquished part was removed--></ref>
|exit_ref=<ref name=CalNexus>{{cite web |first = AS |last = Chand |date = August 26, 2016 |publisher = California Department of Transportation |work = California Numbered Exit Uniform System |url = http://www.dot.ca.gov/trafficops/exit/docs/110.pdf |title = Interstate and State Route 110 Freeway Interchanges |access-date = October 21, 2017 |archive-url = https://web.archive.org/web/20171002070438/http://www.dot.ca.gov/trafficops/exit/docs/110.pdf |archive-date = October 2, 2017 }}</ref>
}}
{{CAint|exit
|location=Los Angeles
|lspan=19
|mile=23.76
|mspan=2
|road={{jct|state=CA|SR|110|dir1=south|name1=[[Harbor Freeway]]|location1=[[Downtown Los Angeles|Downtown]]}}
|notes=Continuation beyond US 101
}}
{{CAint|exit
|mile=none
|exit=24A
|road={{jct|state=CA|US|101|name1=[[Hollywood Freeway]]|I|5|to2=yes|dir2=south|I|10|dir3=east|SR|60|dir4=east|name2=[[Santa Ana Freeway]]|city1=Santa Ana|city2=Hollywood|city3=Ventura}}
|notes=[[Four Level Interchange]]; US 101 north exit 3, south exit 3B
}}
{{CAint|exit
|type=incomplete
|mile=24.49
|exit=24B<!--former 24A-->
|road=[[Sunset Boulevard]]
|notes=Southbound exit and northbound entrance
}}
{{CAint|exit
|mile=24.66
|mspan=2
|type=incomplete
|exit=24C<!--former 24B southbound-->
|road=[[Hill Street (Los Angeles)|Hill Street]]&nbsp;– [[Chinatown (Los Angeles)|Chinatown]], [[Civic Center (Los Angeles)|Civic Center]]
|notes=No southbound entrance; signed as exit 24B northbound; left exit southbound
}}
{{CAint|exit
|mile=none
|exit=24D<!--former 24 northbound/24C southbound-->
|road=Stadium Way&nbsp;– [[Dodger Stadium]]
|notes=Signed as exit 24B northbound
}}
{{CAint|exit
|mile=24.90
|tunnel=[[Figueroa Street Tunnels|Figueroa Street Tunnel No. 1]] (northbound)
}}
{{CAint|exit
|mile=25.02
|exit=25<!--former 25 northbound-->
|road=Solano Avenue / Academy Road
}}
{{CAint|exit
|mile=25.14
|mile2=25.37<!--25.14, 25.28, and 25.37-->
|tunnel=[[Figueroa Street Tunnels|Figueroa Street Tunnels No. 2-4]] (northbound)
}}
{{CAint|exit
|type=incomplete
|mile=25.68
|exit=26A
|road={{Jct|state=CA|I|5|name1=[[Golden State Freeway]]|dir1=north|city1=Sacramento}}
|notes=Northbound left exit and southbound entrance; I-5 south exit 137B
}}
{{CAint|exit
|type=incomplete
|mile=25.71
|exit=26B<!--former 26-->
|road=[[Figueroa Street]]
|notes=Northbound left exit and southbound entrance; former [[California State Route 159|SR&nbsp;159]]
}}
{{CAint|exit
|type=incomplete
|mile=25.84
|exit=26A
|road=Avenue&nbsp;26
|notes=Southbound exit and northbound entrance; former [[California State Route 163 (1964)|SR&nbsp;163]]
}}
{{CAint|exit
|type=incomplete
|mile=
|exit=26B
|road={{Jct|state=CA|I|5|name1=[[Golden State Freeway]]|city1=Santa Ana|city2=Sacramento}}
|notes=Southbound exit and northbound entrance; I-5 north exit 137B, south exit 137A
}}
{{CAint|exit
|mile=27.05
|exit=27
|road=Avenue&nbsp;43
}}
{{CAint|exit
|mile=27.98
|exit=28A
|road=Avenue&nbsp;52
}}
{{CAint|exit
|mile=28.31
|exit=28B
|road=Via Marisol
|notes=Formerly Hermon Avenue
}}
{{CAint|exit
|mile=28.69
|exit=29
|road=Avenue&nbsp;60
}}
{{CAint|exit
|type=incomplete
|mile=29.43
|mspan=2
|exit=30A
|road=Marmion Way&nbsp;/ Avenue&nbsp;64
|notes=Northbound exit and southbound entrance
}}
{{CAint|exit
|type=incomplete
|mile=none
|exit=30
|road=York Boulevard
|notes=Southbound exit and entrance
}}
{{CAint|exit
|type=incomplete
|mile=30.01
|exit=30B
|road=Bridewell Street
|notes=Northbound exit only
}}
{{CAint|exit
|location=South Pasadena
|lspan=2
|mile=30.52
|exit=31A
|road=Orange Grove Avenue
}}
{{CAint|exit
|type=incomplete
|mile=31.10
|exit=31B
|road=[[Fair Oaks Avenue]]
|notes=No northbound entrance
}}
{{CAint|exit
|location=Pasadena
|lspan=5
|mile=31.84
|place=Northern end of freeway
}}
{{CAint|exit
|espan=4
|mile=31.91
|road=Glenarm Street
|notes=Northern end of SR&nbsp;110 and state maintenance
}}
{{CAint
|mile=32.47
|road=California Boulevard
|notes=
}}
{{CAint
|mile=33.05
|road={{jct|state=CA|road|Green Street|I|210|to2=yes}}
|notes=
}}
{{CAint
|mile=33.15
|road=[[Colorado Boulevard]]
|notes=Former [[California State Route 248|SR&nbsp;248]]
}}
{{jctbtm|keys=incomplete,trans}}

==See also==
{{portal|California Roads|Greater Los Angeles|National Register of Historic Places}}
* [[Los Angeles and San Gabriel Valley Railroad]]
{{-}}

== References ==
{{Reflist}}

== External links ==
{{Commons category|Arroyo Seco Parkway}}
{{Attached KML|display=inline, title}}
{{CASR external links}}
* {{HAER |survey=CA-265 |id=ca2755 |title=Arroyo Seco Parkway |photos=41 |color=1 |dwgs=22 |data=86 |cap=6}}
* [[California Department of Transportation]]: [http://www.dot.ca.gov/hq/LandArch/scenic_highways/photos/p_rte110.htm Route 110 Photo Album]
* [[National Scenic Byway]]s: [https://web.archive.org/web/20130824083836/http://byways.org/explore/byways/10246/ Arroyo Seco Historic Parkway – Route 110]
* [http://metroprimaryresources.info/arroyo-seco-parkway-at-70-the-unusual-history-of-the-pasadena-freeway-california-cycleway-rare-traffic-plan-images/852/ Primary Resources – Metro Digital Resources Library: "Arroyo Seco Parkway At 70: The Unusual History Of The "Pasadena Freeway," California Cycleway & Rare Traffic Plan Images"]
* [http://www.arroyoseco.org/index.htm Arroyo Seco Foundation] (environmental preservation group focused on the Arroyo Seco, including information about the parkway)
* [https://web.archive.org/web/20111108003555/http://members.cox.net/mkpl/pasadena/pas.html Mark's Highway Page: Pasadena Freeway] (many current and several historic photos)
* [https://web.archive.org/web/20130516155401/http://www.beatthetraffic.com/traffic/traveltimes.aspx?regionid=2&partner=Time%20Warner%20Cable&header=freemt&ax=true&viewname=SoCal Travel times]
* [https://www.asce.org/about-civil-engineering/history-and-heritage/historic-landmarks/arroyo-seco-parkway American Society of Civil Engineers – National Historic Civil Engineering Landmark]

{{Historic Districts in Los Angeles County}}

[[Category:Arroyo Seco (Los Angeles County)]]
[[Category:Historic Civil Engineering Landmarks]]
[[Category:Historic districts in Los Angeles]]
[[Category:Historic districts on the National Register of Historic Places in California]]
[[Category:History of Los Angeles County, California]]
[[Category:Interstate 10]]
[[Category:Named freeways in California]]
[[Category:National Register of Historic Places in Los Angeles County, California]]
[[Category:National Register of Historic Places in Los Angeles]]
[[Category:National Register of Historic Places in Pasadena, California]]
[[Category:National Scenic Byways]]
[[Category:Northeast Los Angeles]]
[[Category:Parks on the National Register of Historic Places in California]]
[[Category:Roads in Los Angeles County, California]]
[[Category:Roads on the National Register of Historic Places in California]]
[[Category:San Rafael Hills]]
[[Category:Southern California freeways]]
[[Category:State Scenic Highway System (California)]]
[[Category:Transportation in Los Angeles]]
[[Category:Transportation in Pasadena, California]]
[[Category:U.S. Route 66 in California]]