 The land was surveyed in 1715 by the Duke of Marlborough.The first plan of defences was an enceinte (ring of fortifications), from Gun Wharf, Chatham, to north of the village of Brompton.In 1755, the 'Prince of Wales' Bastion, 'Prince Williams Bastion', 'Kings Bastion', 'Prince Edwards Bastion', 'Prince Henry's Bastion' and the 'Prince Fredericks Bastion' were all built.