Events are taking place across England to mark 75 years since HMS Warwick sank during World War Two.
Sixty-six crew members died when the destroyer was hit by a Nazi U-boat's torpedo off the Cornish coast in 1944.
Ken Holmes, 95, thought to be the ship's last survivor, said he lived in a "sad" world without any of his fellow crew.
The men are being remembered at eight events, including services on the Isles of Scilly and at Warwick Castle.
HMS Warwick acted as an escort boat during World War Two, protecting British vessels from German submarine attacks.
It was during these duties that it was hit by a torpedo on 20 February 1944, about 15 miles (24km) off Trevose Head, north Cornwall.
"I was in my mess and I thought there's some trouble here - it's obviously nasty because the ship was shaking," Mr Holmes said, recalling the moment the torpedo hit.
HMS Warwick reportedly sank in just six minutes, but Mr Holmes managed to get off the ship after reaching its upper deck.
"I climbed over and sat on the side of the ship as she went over and I slipped off the bottom into that February water," he said.
He managed to swim away from the ship in the "exceedingly cold" water, he said, before a passing fishing vessel threw him a rope and took him to safety.
Seventy-five years on, the 66 men who died are being remembered at 11:00 GMT at eight remembrance ceremonies across England.
Among the events, people will gather at Padstow Harbour in Cornwall, in the grounds of Warwick Castle and at the Chatham Naval Memorial in Kent.
There will also be services held at the National Memorial Arboretum at Alrewas in Staffordshire, on Plymouth Hoe and at the city's Devonport naval base, Penzance Cemetery and the Old Cemetery on the Isles of Scilly.
Asked how he felt as possibly the ship's last surviving crew member, Mr Holmes said: "Lonely".
"All the others have gone - all my shipmates - so it's a sad old world to live in, once they've all gone," he added.