Faslane Naval Base, situated on the Gare Loch, and the RN Armaments Depot Coulport on Loch Long, are the primary components of HMNB Clyde. The naval shore establishment at Faslane is HMS Neptune, Naval personnel appointed to the base who do not belong to a seagoing vessel make up Ship's Company. Both the Gare Loch and Loch Long are sea lochs extending northwards from the Firth of Clyde. The base serves as home base to Britain's fleet of Vanguard-classnuclear-powered and nuclear-armed submarines, as well as conventionally armed nuclear-powered submarines, supported by the Fleet Protection Group Royal Marines.
In command of HMNB Clyde is the Naval Base Commander (Clyde), Commodore C J Hockley who succeeded Commodore Carolyn Stait in Autumn 2007. The base is home to a number of lodger units including Flag Officer Scotland, Northern England and Northern Ireland (FOSNNI) (who is also Flag Officer Reserves/FORes), the Northern Diving Group and the Scottish Headquarters of theMinistry of Defence Police and Guarding Agency. It is base to 3,000 service personnel, 800 of their families and 4,000 civilian workers, largely from Babcock Marine, forming a major part of the economy of Argyll and Bute and West Dunbartonshire.
Faslane was first constructed and used as a base in World War II. During the 1960s, the British Government began negotiating the Polaris Sales Agreement with the United States regarding the purchase of a Polaris missile system to fire British-built nuclear weapons from five specially constructed submarines. In the end, only four were constructed; HMS Resolution, HMS Repulse, HMS Renown and HMS Revenge. These four submarines were permanently based at Faslane.
Faslane itself was chosen as the base at the height of the Cold War because of its geographic position, which forms a bastion on the relatively secluded but deep and easily navigable Gare Loch and Firth of Clyde on the west coast of Scotland. This position provides for rapid and stealthy access through the North Channel to the submarine patrolling areas in the North Atlantic, through the GIUK gap to the Norwegian Sea. One boat was always on patrol at any given time. In times of political instability, sometimes two boats would be deployed at sea.