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 Banister. During the first decade of the twentieth century LB&SCR station at London Bridge was again enlarged, but overall London Bridge station remained a "sprawling confusion". The chaotic nature of the station at the turn of the century was described in John Davidson's poem, "London Bridge": The South London Line from London Bridge to Victoria was electrified in 1909 with an experimental overhead system. It was successful and other suburban services were electrified including the line to Crystal Palace in 1912. Because of World War I, the line to Croydon was not electrified until 1920. The Railways Act 1921 led