2. Tower Of London
This historic landmark is over 900 years old and arguably London’s most famous structure. It served as an infamous prison where high-level political prisoners would be held or executed. The tower was originally built to keep invaders out.
The main entrance is known as Traitor’s Gate, which you must enter from the River Thames. This building has had over 1,000 years of constant use and it is a symbol of London and Britain. It is now 20 towers forming a defensive stronghold, and for many years, it was the country’s strongest fortress.
When it was built, it was the tallest building in London, and is now home to the crown jewels.