Personnel from HM Naval Base Clyde have remembered those who lost their lives when a Royal Navy submarine sank in 1917.
The memorial service at Faslane Cemetery was attended by Royal Navy personnel, West Scotland Submariners Association and Helensburgh Sea Cadets.
A small gathering was also held in Govan where a monument to shipyard workers who died during the tragedy is situated in Elder Gardens – the dockyard where the early steam-driven submarine K13 was built and launched on 11 November 1916.
Wreaths were laid by members of the West of Scotland Submariners Association and representatives from HMNB Clyde.
The K13 ship's bell was rung during the ceremony – 32 times, once for every person who perished on board.
Reverend Mark Noakes, Chaplain of the Submarine Flotilla, led the service at Faslane Cemetery, also attended by Captain Irvine Lindsay, Captain of the Submarine Flotilla.
Capt Lindsay described early submariners as "genuine pioneers", saying: "Service in those early submarines took great courage and those of us currently serving look to their example of sacrifice and duty with humility and deep respect."
Andy Knox, former Submarine Command warrant officer and chair of the West Scotland Submariner Association, said: "Although this was a great tragedy in the history of the Submarine Service, 42 personnel were rescued from the sunken K13 and lots of valuable lessons were learned for the future of submarine escape."
The submarine sank in the Gareloch on 29 January 1917 with 80 people on board, leading to the death of 32 men, some of them buried at Faslane Cemetery.
Rescue efforts were led by two captains who were on board the stricken submarine when the incident happened.
Lieutenant Commander Godfrey Herbert and K14's captain, Commander Francis Goodhart, attempted to escape from the vessel, in a bid to get help.
Using the space between the inner and outer hatches as an airlock the pair tried to make it to the surface.
Tragically, Commander Goodhart died after striking his head during the escape.
The 57-hour ordeal came to an end when an airline was attached allowing the bow to be raised and a hole cut in the side of the submarine. Forty-eight survivors were rescued.
The submarine was later raised from the Gareloch and returned to service as HMS K22.