The Tower of London is an imposing fortress situated on the north bank of the River Thames in London. This historic castle was founded by William the Conqueror in 1066 and it was initially a basic timber and earth structure. Around 1078 it was remodelled and the structure known as The White Tower was built. There were several phases of expansion under Kings Henry III, Edward I and Richard the Lionheart during the 12th & 13th centuries. The layout that was established then remains the same today.
The Tower is a collection of several buildings set within two concentric rings of defensive walls and a moat. In the beginning it served as a Royal residence but has since been used as a prison, armoury, treasury, the home to the Royal Mint, a public records office, and the home of the Crown Jewels of the United Kingdom. The Tower of London is one of the country's most visited tourist attractions.