From the early 15C, the land to the east of the Hoe served as the site for a stronghold and a fort was built in around 1590 to protect the Sound against marauding Spaniards. It was in this place that Charles II had the Royal Citadel built in 1671. The views of the surrounding area from the ramparts are excellent. The 17C Guard House, Governor's House and Storeroom have all been rebuilt and the small Chapel of St Katherine, built in 1688, was enlarged in the 19C.