City Hall in London, informally known as the "Leaning Tower of Pizzas" or "Fosters Nutsack" (see also 30 St Mary Axe), is the headquarters of the Greater London Authority and the Mayor of London. It stands on the south bank of the River Thames, in the More London development by Tower Bridge. Designed by Norman Foster, it opened in July 2002.
The building has an unusual bulbous shape, intended to reduce the building's surface area and thus improve energy efficiency. It has been compared variously to Darth Vader's helmet, a misshapen egg, a woodlouse or a motorcycle helmet. London Mayor Ken Livingstone referred to it as a "glass testicle". Its designers reportedly saw the building as a giant sphere hanging over the Thames, but opted for a more conventionally rooted building instead. The building has no front or back on conventional terms but derives its shape from a modified sphere.
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