Windsor Castle, the oldest and largest occupied castle in the world, is a must-visit for history nerds and royal enthusiasts. Founded by William the Conqueror in the 11th century, this iconic landmark has been home to 40 monarchs over the years. Visitors can explore the State Apartments, marvel at Queen Mary's Dolls' House, and witness the Changing of the Guard. With its rich history and stunning architecture, Windsor Castle offers a royal experience like no other.

You can get there by train in under an hour (Elizabeth Line to Slough and then the local train 6 mins to Windsor & Eton Central).