The heavy ships of the Italian fleet would be preserved for a potential major battle in the Austro-Hungarian fleet should emerge from its bases. By this time, "Regina Margherita" was long-since obsolescent, and was reduced to a training ship in the 3rd Division, along with her sister ship. On the night of 11–12 December 1916, while sailing from the port of Valona in heavy sea conditions, she struck two mines laid by the German submarine and blew up. There were 270 survivors and 675 men perished. The ship's loss was not announced until January 1917. Lieutenant General Oreste Bandini, the commander of the Italian Albania Expeditionary Corps, was on the ship and was among those who were killed in the sinking.