Which hospital ship, sister of the Titanic, sank in 1916 after hitting a mine?

The hospital ship that sank in 1916 after striking a mine was HMHS Britannic, the Titanic's sister ship.

Britannic was the largest of White Star Line's Olympic-class liners and was originally intended to enter transatlantic passenger service. Before that could happen, the First World War led Britain to requisition her as a hospital ship. She carried wounded soldiers between Britain and the Mediterranean, operating under the prefix HMHS, meaning His Majesty's Hospital Ship.

On 21 November 1916, Britannic struck a German naval mine in the Kea Channel near the Greek island of Kea. The explosion damaged the ship's forward compartments, and she sank in only about 55 minutes. Of the 1,066 people aboard, 30 died and 1,036 survived.

Britannic is often confused with Titanic because both were Olympic-class ships and were built by Harland and Wolff. Britannic was completed after Titanic's 1912 disaster, so her design incorporated additional watertight protections. Unlike Titanic, she sank in wartime while serving as a hospital ship, not as a civilian ocean liner.