HMHS Britannic was the third and largest of the Olympic-Class ocean liners built by Harland & Wolff in Belfast for the White Star Line, following her sister ships Olympic and Titanic. Originally intended as a transatlantic passenger liner, Britannic was still under construction when the First World War broke out. Before she could enter commercial service, Britannic was requisitioned by the British Admiralty and converted into a hospital ship, hence the prefix HMHS – His Majesty’s Hospital Ship. Launched in February 1914 and completed in December 1915, Britannic was fitted with improved safety features in response to the loss of Titanic in 1912. These included an extended double hull, more lifeboats, and improved watertight compartments. Britannic displaced over 48,000 tons, making her the largest ship lost in WWI and at the time, the largest ship afloat. As a hospital ship, Britannic served in the Mediterranean, ferrying wounded soldiers from the front in the Gallipoli campaign back to Britain. On 21 November 1916, during her sixth voyage, Britannic struck a mine laid by a German U-boat near the Greek island of Kea in the Aegean Sea. Despite the ship’s improved safety features, Britannic sank in just 55 minutes. Of the 1,065 people on board, 30 lost their lives, due mostly to a lifeboat mishap involving still-turning propellers. The wreck remains an important underwater heritage site.