Jack Straw's Castle is a relatively new building constructed in the 1960s and is, not by any stretch of the imagination, a castle. It is thought to be named after the leader of the 1381 peasants' revolt who lived on the hill where the "castle" was built.
The former "castle" was destroyed by German bombing in 1941 but dusring its time was a favourite haunt of Charles Dickens, Bram Stoker and Karl Marx.