Tower Bridge 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 exerted 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. Before its restoration in the 2010s, the bridge's colour scheme dated from 1977, when
Tower Bridge day. The bridge is on the London Inner Ring Road, and is on the eastern boundary of the London congestion charge zone. (Drivers do not incur a charge by crossing the bridge.) To maintain the integrity of the structure, the City of London Corporation has imposed a speed restriction, and an weight limit on vehicles using the bridge. A camera system measures the speed of traffic crossing the bridge, using a number plate recognition system to send fixed penalty charges to speeding drivers. A second system monitors other vehicle parameters. Induction loops and piezoelectric sensors are used to measure the