EDITED TO ADD: Please, please, please don't ride elephants. Find another way to support them like helping get them into sanctuaries, not serving tourists. Jaipur, India...an Indian elephant ride all the way up to the Great Amber (Amer) Hindu Fort and Palace.
Windsor Castle, parts of which date back to the 11th century, is a royal residence at Windsor in the English county of Berkshire. The castle is notable for its long association with the British royal family and for its architecture. The original castle was built after the Norman invasion by William the Conqueror