The remains of the Castle can be visited
CastleIsle of Portland
Rufus Castle

Rufus Castle, also known as Bow and Arrow Castle, is a ruined castle overlooking Church Ope Cove on Portland, England. The castle is a Grade I listed building, dating from the late 15th century, on the site of an earlier building - making it Portland's oldest castle.
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Location: 50.5395, -2.4283