The Flaghouse and a series of Privies were built close to the original landing place near what is now Kingston Pier in the 1840's for the purposes of storing the settlement flag collection of multi-coloured flags. These flags were used to signal boats offshore to assist safe passage across the narrow entrance through the reef to the shore.
Flags were used until the 1950's. A red flag on Flagstaff Hill meant - land at Cascade on the other side of the island. A white flag meant safe to land at Kingston.
Both red and white Flags flown together meant unsafe to land at Kingston.