1665 - founded at the mouth of the River Medway, initially for storing and refitting ships. 1673 - first dry dock completed. 1691 - Sheerness launched – small fifth rate of 32 guns. 1739 - a large fire occurred, started by the sale of spirits within the yard. 1720 - a second dry dock was built and it became a ship construction yard, mainly for fourth- and fifth-rate ships. 1815 – dockyard rebuilding commenced. 1823 - dockyard modernisation completed and opened by the, then, Duke of Clarence, soon to be King George IV. 1830 - a riot broke out when a dock worker was accused of 'being in possession of the King's stores' by a Warden. 1832 - the steam powered paddle sloop Salamander launched. 1854 - a steam yard was established. 1859 - the iron-framed Boathouse built. 1905 - The Actaeon was commissioned at Sheerness as a Torpedo School. 1915 - while work was being completed on the Princess Irene, a badly primed mine exploded, causing a chain reaction, which killed 170 dockyard workers and ripped the docked fleet of submarines and destroyers apart. 1957 - the yard closed.