Tower Bridge is a combined bascule and suspension bridge in London, built between 1886 and 1894. The bridge crosses the River Thames close to the Tower of London and St Katharine Docks and has become a world-famous symbol of London. As a result, it is sometimes confused with London Bridge, about 0.5 miles (0.80 km) upstream. Tower Bridge is one of five London bridges owned and maintained by the Bridge House Estates, a charitable trust overseen by the City of London Corporation. It is the only one of the trust’s bridges not to connect the City of London directly to the Southwark bank, as its northern landfall is in Tower Hamlets.
The bridge consists of two bridge towers tied together at the upper level by two horizontal walkways, designed to withstand the horizontal tension forces imposed by the suspended sections of the bridge on the landward sides of the towers. The vertical components of the forces in the suspended sections and the vertical reactions of the two walkways are carried by the two robust towers. The bascule pivots and operating machinery are housed in the base of each tower.
The Tower Bridge Exhibition is a display housed in the bridge’s twin towers, the high-level walkways and the Victorian engine rooms. It uses films, photos and interactive displays to explain why and how Tower Bridge was built. Visitors can access the original steam engines that once powered the bridge bascules, housed in a building close to the south end of the bridge. The exhibition charges an admission fee. Entrance is from the west side of the bridge deck to the northern tower, from where visitors ascend to level 4 by lift before crossing the high-level walkways to the southern tower. In the towers and walkways is an exhibition on the history of the bridge. The walkways also provide views over the city, the Tower of London and the Pool of London, and include a glass-floored section. From the south tower, visitors can visit the engine rooms, with the original steam engines, which are situated in a separate building beside the southern approach to the bridge.