The site of Carisbrooke Castle may have been occupied in pre-Roman times. The existence of a ruined wall suggests there was a building there in late Roman times. An Anglo-Saxon stronghold occupied the site during the 8th century. Around 1000, a wall was built around the hill as a defence against Viking raids. The Norman castle is from 11th century.Surrounding the whole castle are large earthworks, designed by the Italian Federigo Gianibelli, and begun in the year before the Spanish Armada. They were finished in the 1590s.