Tower is any structure that is relatively tall in proportion to the dimensions of its base.
It may be either freestanding or attached to a building or wall. Modifiers frequently denote a tower’s function (e.g., watchtower, water tower, church tower, and so on).
Old English torr is from Latin turris via Old French tor. The Latin term together with Greek τύρσις was loaned from a pre-Indo-European Mediterranean language, connected with the Illyrian toponym Βου-δοργίς.
From the legendary Tower of Babel to the iconic Burj Khalifa, humans have always aspired to build to ever greater heights. Over the centuries, we have constructed towering edifices to celebrate our culture, promote our cities – or simply to show off.
The oldest known tower may be the circular stone tower in walls of Neolithic Jericho (8000 BC). Some of the earliest towers were ziggurats, which existed in Sumerian architecture since the 4th millennium BC. The most famous ziggurats include the Sumerian Ziggurat of Ur, built the 3rd millennium BC, and the Etemenanki, one of the most famous examples of Babylonian architecture. The latter was built in Babylon during the 2nd millennium BC and was considered the tallest tower of the ancient world.
Defensive towers served as platforms from which a defending force could rain missiles down upon an attacking force. The Romans, Byzantines, and medieval Europeans built such towers along their city walls and adjoining important gates. The Romans and other peoples also used offensive, or siege, towers, as raised platforms for attacking troops to overrun high city walls. Military towers often gave their name to an entire fortress – the Tower of London, for example, includes the entire complex of buildings contiguous with the White Tower of William I the Conqueror.
In history, simple towers like lighthouses, bell towers, clock towers, signal towers and minarets were used to communicate information over greater distances. In more recent years, radio masts 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. Its design also incorporated features to make it a tourist attraction, including the world’s highest observation deck at 147 storeys.
Towers were an important feature of the churches and cathedrals built during the Romanesque and Gothic periods. Some Gothic church towers were designed to carry a spire, while others had flat roofs. Many church towers were used as belfries, though the most famous campanile, or bell tower, the Leaning Tower of Pisa (1174), is a freestanding structure.
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 bridges and cable-stayed bridges. The use of the pylon, a simple tower structure, has also helped to build railroad bridges, mass-transit systems, and harbors.
Although not correctly defined as towers, many modern high-rise buildings (in particular 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 had the nickname the Twin Towers, a name shared with the Petronas Twin Towers in Kuala Lumpur.
Tokyo Skytree is a broadcasting and observation tower in Sumida, Tokyo. It became the tallest structure in Japan in 2010 and reached its full height of 634 meters (2,080 ft) in March 2011, making it the tallest tower in the world, displacing the Canton Tower, and the third tallest structure in the world after the Merdeka 118 (678.9 m or 2,227 ft) and the Burj Khalifa (829.8 m or 2,722 ft). It is also the tallest freestanding structure in the OECD.
The Canton Tower, formally Guangzhou TV Astronomical and Sightseeing Tower, is a 604-meter (1,982 ft)-tall multipurpose observation tower in the Haizhu District of Guangzhou (alternatively romanized as Canton). The tower was topped out in 2009 and it became operational on 29 September 2010 for the 2010 Asian Games. The tower briefly held the title of tallest tower in the world, replacing the CN Tower, before being surpassed by the Tokyo Skytree. It was the tallest structure in China prior to the topping out of the Shanghai Tower on 3 August 2013, and is now the second-tallest tower and the fourth-tallest freestanding structure in the world.