Built in 1078 by William the Conqueror, the Tower of London has been at the heart of the city for over 900 years. It’s been a palace, a fortress, a military garrison, a prison, and today it’s home to the Crown Jewels, which are carefully guarded by the Beefeaters. With over 2.5 million visitors a year, the Tower of London is a must-see site for all people visiting the capital of the UK, and you can save time and money when you book your trip in advance.