The Probert Encyclopaedia of Architecture

TOWER OF LONDON

The Tower Of London is an ancient fortress on the left bank of the River Thames in London, on a site of some thirteen acres. The present castle has a keep, known as the White Tower, which was built as a fortress by William The Conqueror beiween 1078 and 1080 on a site of a previous Roman fortress. The Tower of London was a royal palace in the Middle Ages, and was later used as a garrison and prison. The Crown Jewels are kept at the Tower Of London.
Research Tower of London