Windsor Castle, the oldest and largest occupied castle in the world, is a must-visit for history buffs and royal enthusiasts alike. Founded by William the Conqueror in the 11th century, this iconic landmark has been home to 40 monarchs over the years. From the State Apartments to Queen Mary's Dolls' House, there's no shortage of fascinating things to see and do at Windsor Castle. Plus, don't forget to grab a cuppa and some cake at the Undercroft Café – it's the perfect pit stop in between exploring centuries of royal history!