The ArcelorMittal Orbit is a 115-metre-high (377 ft) sculpture and observation tower in the Olympic Park in Stratford, London. It is Britain's largest piece of public art, and is intended to be a permanent lasting legacy of London's hosting of the 2012 Summer Olympics, assisting in the post-Olympics regeneration of the Stratford area. Sited between the Olympic Stadium and the Aquatics Centre, it allows visitors to view the whole Olympic Park from two observation platforms.
Orbit was designed by Anish Kapoor and Cecil Balmond of engineering Group Arup. Announced on 31 March 2010, it was expected to be completed by December 2011. The project came about after Mayor of London Boris Johnson and Olympics Minister Tessa Jowell decided in 2008 that the Olympic Park needed "something extra". Designers were asked for ideas for an "Olympic tower" at least 100 metres (330 ft) high, and Orbit was the unanimous choice from proposals considered by a nine-person advisory panel.[Source]