Tower Bridge is managed by the City of London Corporation, the sole trustee of the charity Bridge House Estates. The City of London Corporation is older than Parliament and its experience and tradition underpin its modern role as the provider of key services. Elected Members, headed by the Lord Mayor, operate on a non-party political basis.

Tower Bridge was constructed over 125 years ago by Bridge House Estates, which is now one of London’s largest independent charities.

Built between 1886 and 1894, the Bridge has spent more than a century as London's defining landmark, an icon of London and the United Kingdom.

www.towerbridge.org.uk

The bridge is 800 feet (240 m) in length and consists of two 213-foot (65 m) bridge towers connected at the upper level by two horizontal walkways, and a central pair of bascules that can open to allow shipping. Originally hydraulically powered, the operating mechanism was converted to an electro-hydraulic system in 1972. The bridge is part of the London Inner Ring Road and thus the boundary of the London congestion charge zone, and remains an important traffic route with 40,000 crossings every day. The bridge deck is freely accessible to both vehicles and pedestrians, whereas the bridge's twin towers, high-level walkways and Victorian engine rooms form part of the Tower Bridge Exhibition.

en.wikipedia.org