HMS Forth, pennant number F04 later A187, was a submarine depot ship.
She was completed in 1939. Forth served at Holy Loch on the Clyde for a period during the Second World War. Subsequently Forth was stationed at Trincomalee, Ceylon during the end of the Second World War.
During the war Forth was adopted by Stirlingshire as part of Warship Week. The plaque from this adoption is held by the National Museum of the Royal Navy in Portsmouth.
During her stay in Malta in the 1950s she was moored on the east side of Msida creek. In 1953 she took part in the Fleet Review to celebrate the Coronation of Queen Elizabeth II. She left Malta in 1960.
She was modified to support the Royal Navy's nuclear-powered submarines at H.M.Dockyard Chatham between 1962-1966.
She arrived in Singapore in mid-1966 to relieve HMS Medway (former Landing craft tank HMS LCT 1109) as depot ship of the 7th Submarine Squadron. She left Singapore to return to the UK 31 March 1971.
HMS Forth took the first Hovercraft to Australia in 1968, a small two or three seater.