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 Is Falling Down is an earlier version of the nursery rhyme. Some historians have raised the possibility that the attack never took place. However, the original document detailing the attack was written only about 100 years after what would be a famous event in a highly populated area, leading the majority of historians to conclude that the account is at least relatively accurate. While it might or might not be the origin of the rhyme, this would make King Olaf's victory the only historically recorded incidence of London Bridge "falling down." The theory that the song refers to the burying, perhaps alive, of