Bridge four-lane highway on the upper level and a pair of railway tracks at the lower level. Tower Bridge in London is different example of a double-decked bridge, with the central section consisting of a low level bascule span and a high level footbridge. A viaduct is made up of multiple bridges connected into one longer structure. The longest and some of the highest bridges are viaducts, such as the Lake Pontchartrain Causeway and Millau Viaduct. A three-way bridge has three separate spans which meet near the center of the bridge. The bridge appears as a "T" or "Y" when viewed
London Bridge station to the Big Four grouping in 1923. All of the railways of southern England combined to form the Southern Railway (SR), bringing the London Bridge complex under single ownership. The wall that divided the Chatham and Brighton stations was partially knocked through in 1928 to provide an easier interchange between stations. This allowed a greater range of platforms to be used for the increasingly frequent suburban rail services to London Bridge. Between 1926 and 1928 the Southern Railway electrified the SE&CR suburban lines at London Bridge using a third rail system, adapting the existing LB&SCR routes to it at the