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{{Redirect|Towers||Tower (disambiguation)}}
{{Short description|Structure with height greater than width}}
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{{More citations needed|date=June 2023}}
[[File:Tokyo Sky Tree 2012.JPG|thumb|[[Tokyo Skytree]], the [[List of tallest towers in the world|tallest tower in the world]]]]
[[File:Römerturm, Auf dem Gaulskopf.jpg|thumb|[[Ancient Rome|Roman]] tower ([[Reconstruction (architecture)|reconstruction]]) at [[Upper Germanic-Rhaetian Limes|Limes]] – [[Taunus]] / Germany]]

A '''tower''' is a tall [[Nonbuilding structure|structure]], taller than it is wide, often by a significant factor. Towers are distinguished from [[guyed mast|masts]] by their lack of [[guy-wires]] and are therefore, along with tall buildings, self-supporting structures.

Towers are specifically distinguished from [[building]]s in that they are built not to be habitable but to serve other functions using the [[height]] of the tower. For example, the height of a [[clock tower]] improves the visibility of the clock, and the height of a tower in a fortified building such as a [[castle]] increases the visibility of the surroundings for defensive purposes. Towers may also be built for [[observation tower|observation]], leisure, or [[telecommunication]] purposes. A tower can stand alone or be supported by adjacent buildings, or it may be a feature on top of a larger structure or building.

==Etymology==
[[Old English]] ''torr'' is from [[Latin]] ''turris'' via [[Old French]] ''tor''. The Latin term together with [[Greek language|Greek]] τύρσις was loaned from a pre-Indo-European Mediterranean language, connected with the [[Illyrian language|Illyrian]] toponym
Βου-δοργίς. With the [[Lydian language|Lydian]] toponyms Τύρρα, Τύρσα, it has been connected with the ethnonym [[Tyrrhenians|Τυρρήνιοι]] as well as with ''Tusci'' (from ''*Turs-ci''), the Greek and Latin names for the [[Etruscans]] (Kretschmer Glotta 22, 110ff.)

==History==
Towers have been used by humankind since prehistoric times. The oldest known may be the circular stone tower in walls of [[Wall of Jericho (Neolithic)|Neolithic Jericho]] (8000 BC). Some of the earliest towers were [[ziggurat]]s, which existed in [[Sumerian architecture]] since the 4th millennium BC. The most famous ziggurats include the Sumerian [[Ziggurat of Ur]], built in the 3rd millennium BC, and the [[Etemenanki]], one of the most famous examples of [[Art and architecture of Assyria|Babylonian architecture]]. 

Some of the earliest surviving examples are the [[broch]] structures in northern [[Scotland]], which are conical [[towerhouse|tower house]]s. These and other examples from [[Phoenicia]]n and [[Ancient Rome|Roman]] cultures emphasised the use of a tower in fortification and sentinel roles. For example, the name of the Moroccan city of [[Mogador]], founded in the first millennium BC, is derived from the Phoenician word for [[watchtower]] ('migdol'). The Romans utilised octagonal towers<ref>{{cite web|url=http://www.megalithic.co.uk/article.php?sid=17691|title=Diocletian's Palace|first=The Megalithic Portal and Megalith|last=Map|website=The Megalithic Portal}}</ref> as elements of [[Diocletian's Palace]] in [[Croatia]], which monument dates to approximately 300 AD, while the [[Servian Walls]] (4th century BC) and the [[Aurelian Walls]] (3rd century AD) featured square ones. The Chinese used towers as integrated elements of the [[Great Wall of China]] in 210 BC during the [[Qin dynasty]]. Towers were also an important element of [[Towers in medieval fortifications|castles]].

[[File:The Eiffel Tower, Paris, France.jpg|thumb|right| [[Eiffel Tower]] in Paris]]

Other well known towers include the [[Leaning Tower of Pisa]] in [[Pisa, Italy]] built from 1173 until 1372, the [[Two Towers, Bologna|Two Towers]] in [[Bologna, Italy]] built from 1109 until 1119 and the [[Towers of Pavia]] (25 survive), built between 11th and 13th century. The [[Himalayan Towers]] are stone towers located chiefly in [[Tibet]] built approximately 14th to 15th century.
<ref>[https://web.archive.org/web/20040409183554/http://msnbc.msn.com/id/3474951/ Dana Thomas, "Towers to the Heavens"], ''Newsweek'', 2003-11-15</ref>

==Mechanics==
[[File:Torre Monumental - Día neblinoso.jpg|thumb|The [[Torre Monumental|Monumental Tower]] in a foggy day in [[Buenos Aires]], [[Argentina]]]]
Up to a certain height, a tower can be made with the supporting structure with parallel sides. However, above a certain height, the compressive load of the material is exceeded, and the tower will fail. This can be avoided if the tower's support structure tapers up the building.

A second limit is that of buckling—the structure requires sufficient stiffness to avoid breaking under the loads it faces, especially those due to winds. Many very tall towers have their support structures at the periphery of the building, which greatly increases the overall stiffness.

A third limit is dynamic; a tower is subject to varying winds, vortex shedding, seismic disturbances etc. These are often dealt with through a combination of simple strength and stiffness, as well as in some cases [[tuned mass damper]]s to damp out movements. Varying or tapering the outer aspect of the tower with height avoids vibrations due to vortex shedding occurring along the entire building simultaneously.

==Functions==
Although not correctly defined as towers, many modern [[high-rise building]]s (in particular [[skyscrapers|skyscraper]]) have 'tower' in their name or are colloquially called 'towers'. Skyscrapers are more properly classified as 'buildings'. In the [[United Kingdom]], tall domestic buildings are referred to as '''tower blocks'''. In the [[United States]], the original [[World Trade Center (1973–2001)|World Trade Center]] had the nickname the Twin Towers, a name shared with the [[Petronas Twin Towers]] in [[Kuala Lumpur]]. In addition some of the structures listed below do not follow the strict criteria used at [[List of tallest towers]].

===Strategic advantages===
The tower throughout history has provided its users with an advantage in surveying defensive positions and obtaining a better view of the surrounding areas, including battlefields. They were constructed on [[defensive walls]], or rolled near a target (see [[siege tower]]). Today, strategic-use towers are still used at prisons, military camps, and defensive perimeters.

===Potential energy===
By using gravity to move objects or substances downward, a tower can be used to store items or liquids like a [[storage silo]] or a [[water tower]], or aim an object into the earth such as a [[drilling tower]]. [[ski jumping|Ski-jump ramps]] use the same idea, and in the absence of a natural mountain slope or hill, can be human-made.

===Communication enhancement===
In history, simple towers like [[lighthouse]]s, [[bell tower]]s, [[clock tower]]s, [[Signal box|signal towers]] and [[minaret]]s were used to communicate information over greater distances. In more recent years, [[radio mast]]s and cell phone towers facilitate communication by expanding the range of the transmitter. The [[CN Tower]] in [[Toronto, Ontario]], Canada was built as a communications tower, with the capability to act as both a transmitter and repeater. Telecom towers are designed with a [[latticework|lattice]] structure to evenly distribute their entire load especially in windy conditions.<ref>{{cite conference |last1=John |first1=Vinotha Jenifer |last2=S. |first2=Nisha |last3=M. |first3=Sobicka |last4=O. |first4=Anandavalli |title=A Comparative Study Of Telecommunication Tower Subjected To Static Analysis With Different Member Cross Section |url=https://iopscience.iop.org/article/10.1088/1757-899X/1333/1/012001 |conference=2nd National Conference on Structural and Geotechnical Engineering 2024 |location=Jamshedpur, Jharkhand, India |date=6–7 September 2024 |volume=1333 |issue=1 |pages=1-6 |doi=10.1088/1757-899X/1333/1/012001}}</ref>

===Transportation support===
Towers can also be used to support bridges, and can reach heights that rival some of the tallest buildings above-water. Their use is most prevalent in [[suspension bridge]]s and [[cable-stayed bridge]]s. The use of the pylon, a simple tower structure, has also helped to build railroad bridges, mass-transit systems, and harbors.

[[Control tower]]s are used to give visibility to help direct aviation traffic.

===Other===
* To access tall or high objects: [[launch tower]], [[service tower]], [[service structure]], [[scaffolding|scaffold]], [[tower crane]]
* To access atmospheric conditions aloft: [[wind turbine]], meteorological [[measurement tower]], [[tower telescope]], [[solar thermal energy|solar power]] station
* To lift high tension cables for electrical power distribution [[transmission tower]]
* To take advantage of the temperature gradient inherent in a height differential: [[cooling tower]]
* To expel and disperse potentially harmful gases and particulates into the atmosphere: [[chimney]]
* To protect from exposure: [[BREN Tower]], [[lightning rod tower]]
* For industrial production: [[shot tower]]
* For surveying: Survey tower
* To drop objects: [[Drop tube]] (drop tower), [[bomb tower]], [[high diving|diving platform]]
* To test height-intensive applications: [[Express Lift Tower|elevator test tower]]
* To improve structural integrity: [[thyristor tower]]
* To mimic towers or provide height for training purposes: [[fire tower]], [[parachute tower]]
* As art: [[Shukhov Tower]]
* For recreation: [[rock climbing|rock climbing tower]]
* As a symbol: [[Tower of Babel]], [[The Tower (Tarot card)]], [[steeple|church tower]]

The term "tower" is also sometimes used to refer to firefighting equipment with an extremely tall ladder designed for use in firefighting/rescue operations involving high-rise buildings.

==Gallery==
{{gallery
|File:Galata tower 01 23.jpg|The [[Galata Tower]], also called ''Christea Turris'' (the Tower of Christ in Latin), was built in 1348 A.D. by the [[Republic of Genoa|Genoese]] colony in [[Constantinople]].
|File:Carmel-indiana-water-tower.jpg|Typical modern water tower in [[Carmel, Indiana]], United States
|File:Nasinneula Mustalahti Tampere Finland.jpg|[[Näsinneula]], an [[observation tower]] in [[Tampere]], [[Finland]], at night
|File:Israeli West Bank barrier watchtower.jpg|Watchtower in the [[Israeli West Bank barrier]]
|File:Bratislava - Most SNP (c).JPG|The only bridge being a member of the [http://www.great-towers.com/ World Federation of Great Towers]: [[Most SNP]], [[Bratislava]], [[Slovakia]]
|File:Caucasus, Ingushetia, Ингушские боевые и смотровые башни, горы Кавказа.jpg|Medieval military towers from [[Ingushetia]], [[Caucasus Mountains]]
|File:Lifeguard tower, Asprovalta.jpg|[[Lifeguard|Lifeguard tower]], [[Asprovalta]] (Greece)
|File:An access road at Minsca Wind Farm - geograph.org.uk - 994215.jpg|The towers of wind turbines support the rotors.
|File:Brixen_Weisser_Turm_02.JPG| [[White Tower (Brixen)]]-Italy built in 1591
|File:Pvtorri.jpg| Some of the [[Towers of Pavia]], 11th-13th century
|File:Hameenlinna Aulanko Nature Reserve tower.jpg|The Aulanko Tower at the [[Aulanko Nature Reserve]] in [[Hämeenlinna]], Finland
|File:Torre Racef (Almussafes).jpg|Rassef Islamic tower, [[Almussafes]]
||title=}}

==See also==

===General===
* [[Additionally guyed tower]]
* [[Bell tower]]
* [[Inclined towers]]
* [[List of tallest towers in the world]]
* [[Observation tower]]
* [[Partially guyed tower]]
* [[Smog tower]]
* [[Spire]]
* [[Tower house]]
* [[Twin towers (architecture)]]
* [[World's tallest structures]]

===Warfare===
* [[Battery tower]]
* [[Bergfried]]
* [[Breaching tower]]
* [[Butter-churn tower]]
* [[Flanking tower]]
* [[Fortified tower]]
* [[Gate tower]]
* [[Turret (architecture)|Turret]]
* [[Watchtower]]
* [[Wall tower]]

==References==
{{reflist}}

==Further reading==
* Fritz Leonhardt (1989), ''Towers: a historical survey'', Butterworth Architecture, 343 pages.

==External links==

{{commons category|Towers}}

{{Authority control}}

[[Category:Towers| ]]