The tall, stone-built keep has retained much of its original appearance: Romanesque vaults, its windows, oratory and a 34m-deep well. A tour of the castle takes you from the battlements to the dungeons, where an exhibition charts the history of the city. The art gallery on the ground floor presents an impressive collection of works from the Norwich School, created in the early 19C by local self-taught artist, John Crome (1768-1821).