The third fort that protected St. John's harbour was built on Rat Island, close to the city and is the easternmost defense point of the triad of forts protecting the harbour.  On December 10th 1672, Sir William Stapleton reported that he had setup a small fort on a little island in St. John's.  Indeed on early maps of Antigua, Rat Island is known as Fort Island.  The fort had been started on the first Monday in September, as that had been the day appointed for each plantation owner to provide one slave in eight on the island with axe and bill for clearing prior to building.  So "Ratt Island" was one of the first forts of Antigua.