The Royal Marines who were responsible for the protection of the Dockyard had been quartered in an old ship called the Dragon. In 1844 work commenced to build them a more permanent home at a site overlooking the Dockyard on what came to be called Barrack Hill. Work on this massive building was somehow completed within a year and the Defensible Barracks, as they were called, were handed over to the military in November 1845. This was an artillery fort, not just a barracks, and a number of nearby buildings were demolished to give its guns a clear line of fire. The Defensible Barracks was surrounded by a deep open moat into which, according to local stories, a number of soldiers fell whilst returning from visits to local hostelries. The Defensible Barracks continued to be occupied by troops until the mid 1950s and the building still stands in its vantage point high above the town.