The 19th Century saw the establishment of a Royal Naval base in Bermuda. Initially this was in St. George's Harbour, with the Royal Navy operating from facilities in Convict Bay (so called due to the prison hulks moored there) and within St. George's town. This build up began in 1795, but a decade later, the Royal Navy was actively developing the dockyard on Ireland Island, and it soon withdrew from St. George's completely. The buildup of the dockyard at the West End of the archipelago still resulted in considerable defence infrastructure around St. George's, at the East End, however, as this was the gateway through the surrounding reefs to all of Bermuda. In addition to the 17th and 18th century forts built by the militia, there are many 19th and 20th Century forts and batteries built by the regular British Army on the islands surrounding the harbour, for which Ordnance Island was the primary ammunition depot. The various surviving East End forts, batteries and other military structures, together with the old capital, have been declared by the United Nations Educational, Scientific and Cultural Organization as a World Heritage Site, the .