name of the final and defining battle of the Turkish War of Independence. After serving Turkey for close to three years, TCG Dumlupınar was lost due to an accident on 4 April 1953, when, while returning from the NATO training mission "Blue Sea", she collided with the Swedish freighter M/V Naboland off Nara Point in the Dardanelles and sank. Ninety-four submariners died in the accident due to drowning, bodily injury, and carbon dioxide poisoning. Presently, the TCG Dumlupınar, along with its perished crew, lies at a depth of 90 meters. The Dumlupınar Tragedy Late evening on 3 April 1953, Turkish submarines TCG İnönü I and TCG Dumlupınar started their voyage home to the TAF Naval Yards in Gölcük after completing their respective missions in a regular NATO training exercise in the Mediterranean. On 4 April 1953 at 02:10am, they entered the Dardanelles (aka, Çanakkale Strait) en route to Gölcük with 96 crew members - 88 men inside the vessel, and 8 men on deck. There was heavy mist in the strait that night, which severely limited visibility. Lieutenant Hüseyin İnkaya was on deck duty when the Dumlupınar was suddenly and violently struck by something unseen off Nara point - the narrowmost (1.2 km, 0.75 mi) and deepest (113 m, 370 ft) point of the Dardanelles, as well as the point where the currents are the strongest at up to 5 nautical miles versus 1–2 elsewhere on the strait. The eight crew members who were on deck at the moment of collision were thrown off into the water from the force of the impact, with two crew members being killed by the submarine's propellers, while another drowned in the ensuing commotion. Dumlupınar had been rammed by Swedish cargo ship M/V Naboland in her bow torpedo room on the starboard side, and started to take water in her front compartments. Due to the scale of the damage caused and the subsequent explosion in her central compartment, Dumlupınar sank within minutes. Most communications were severed along with her electrical power. The 88 surviving men inside the submarine, seeing that the vessel was taking water from the bow, tried to reach the stern to seek shelter in the torpedo room, with many of them perishing in the rapidly rising waters. Of the original 88, only 22 were able to reach and lock themselves in the stern torpedo compartment, and released an emergency communications buoy