Tower Bridge was officially opened on June 30, 1894, by the Prince of Wales, who later became King Edward VII.
The bridge took eight years to construct, with over 11,000 tons of steel used in its framework.
Tower Bridge is often mistaken for London Bridge, which is actually a different bridge further upstream.
The iconic twin towers are connected by two walkways that provide stunning views of the River Thames.
The bridge was originally powered by steam engines that operated the bascules, which could be raised to allow ships to pass through.
In 1976, the steam engines were replaced with a more modern electro-hydraulic system.
The high-level walkways were closed to the public in 1910 due to lack of use but were reopened in 1982 as part of the Tower Bridge Exhibition.
During World War II, Tower Bridge was camouflaged to protect it from enemy air raids.
The bascules, or the movable sections of the bridge, still open about 1,000 times a year.
The bridge is painted in a distinctive red, white, and blue color scheme, a change made in 1977 to celebrate Queen Elizabeth II's Silver Jubilee.
A London bus famously jumped across the opening bascules in 1952 when the bridge began to rise unexpectedly.
The bridge has appeared in numerous films, including 'The Mummy Returns' and 'Mission: Impossible'.
Tower Bridge is a Grade I listed structure, indicating it is of exceptional historical importance.
A glass floor was added to the walkways in 2014, offering a unique view of the bridge and the river below.
Tower Bridge's design was chosen from over 50 submitted designs in a public competition held in the 19th century.