 A fort situated at that point could thus provide an effective defence against an enemy attempting to land here.It also served to fill the gap between the upriver forts (Cliffe, Coalhouse and Shornemead) and those at the mouth of the Medway (Grain and Garrison Point).As an 1869 report noted, the fort was constructed "to prevent an enemy landing at the only accessible point for the purpose of attacking Chatham Dockyard from the north".