Built by William the conquerer in 1068 and still standing tall.
The majority of of this attraction has been turned into a theme park for children, but the main tower is where you’ll see historic exhibitions of how things would have looked.
The video below (not great I know, but it might give you an idea of what to expect).
Dungeons, Bird of Prey Show, a maze, and various other attractions will keep you busy if staying for a full day.