The round tower at Windsor castle in Berkshire

Windsor Castle is a royal residence at Windsor in the English county of Berkshire. It is notable for its long association with the English and British royal family and also for its architecture. The original castle was built in the 11th century after the invasion by William the Conqueror. Since the time of Henry I, it has been used by succeeding monarchs and is the longest-occupied palace in Europe. The castle's lavish, early 19th century State Apartments are architecturally significant, and is described as a superb and unrivalled sequence of rooms widely regarded as the finest and most complete expression of later Georgian taste. Photographed using Nikon-D800E (36 megapixels) DSLR with AF-S NIKKOR 24-70 mm f/2.8G ED lens at focal length 24 mm, ISO 100, and exposure 1/1600 sec at f/2.8.