Tower Bridge

Tower Bridge was built between 1886 and 1894 and is one of the United Kingdom's most recognisable landmarks. The Bridge is often mistakenly called London Bridge, which lies to the west along the River Thames.
The bridge is an example of a bascule bridge. About 3 times a day the Bridge is required to open to allow for access and egress to London for vessels with a mast or structure of 30 feet or more. The vessels must give 24 hours notice for the bascules to lift.