The line to get into the castle might be crazy long but I really think it’s worth the wait. The ticket to get in is £24 (around $32). Windsor Castle is the largest and oldest fortress in the world and it’s quite majestic. It’s still being used for state occasions and is one of Queen Elizabeth’s residences. I recommend you take the free guided tour (taking place every half hour). While you’re there, don’t miss Queen Mary’s Doll’s House, the State Apartments, St. George’s Chapel, and the changing of the guard ceremony.