The White Tower

An interesting day at the Tower of London. This is the central Norman building, the White Tower. Although started by William the Conqueror  he never saw it completed. It used to be whitewashed - on the orders of Henry III - hence the name.  Although the castle looks rectangular, it actually has a semi-circular section (as seen here) to accommodate the apse of St John's Chapel on the first floor, which is the oldest church in use in London.