The sinking of the Andrea Doria took place on July 26th, 1956. She was going from Italy to New York, that was her 51th crossing, the Italian liner was with 1.134 passengers on board. Two days earlier, the Swedish American Liner, Stockholm, departed from New York en route to Sweden, both ships were in a highly used transatlantic route. At 11:10 PM, after that both ships were desperately trying to avoid the collision, the Stockholm hit the Andrea Doria on its starboard side making a 12 metres deep hole. 51 people lost their lives, lifeboats from the Stockholm were lowered to help the desperate passengers of the Italian Liner. The ship took over 10 hours to sink and it's considered one of the worst maritime disasters during times of peace.
Video from the British Movietone Archives.