What William the Conqueror castles are still around today?

Several castles built by William the Conqueror still stand today, most notably the Tower of London, which served as a royal palace and fortress. Another significant example is the White Tower, also part of the Tower of London complex. Additionally, his castle at Windsor, which has been expanded and renovated over the centuries, remains a prominent royal residence. These structures highlight the Norman influence on medieval architecture in England.