For nearly 2000 years London has been the most important city in Britain. Its position on the River Thames has turned it into an international port and a centre for finance, trade, industry, arts and government. The Tower of London was a former royal residence which later served as a prison. The Monument commemorates the fire in 1666, which consumed most of the old City. With the re-building came many famous churches, including St. Paul's Cathedral. In London you can find the Houses of Parliament and Buckingham Palace. In the west there are many famous stores like Harrods, and other fashionable areas such as Kensington and Chelsea. It is a city where old and new live together.