On July 17 1956 passengers began boarding the Andrea Doria as she waited in the Genoa pier to begin her 51st crossing from Italy to New York. The ship departed at 11:00 a.m. The Doria stopped in Cannes on the French Riviera, then Naples, then Gibraltar before leaving the Mediterranean and heading west into the North Atlantic ocean. There were 1,134 passengers in total on the ship in addition to hundreds of pieces of baggage, freight, and other cargo. The Doria’s captain — Captain Piero Calamai — had more than 40 years experience at sea. Calamai had a crew of 572, who took care of the ship and who also served the passengers as they indulged in the luxurious lifestyle the Doria had to offer. As the Doria neared its ultimate destination passengers and crew alike were preparing for the ship’s scheduled arrival in New York at 9:00 a.m on Thursday, July 26.

During the summer, the area off Nantucket known as Times Square (because of all the ship traffic that passes through it) is often riddled with fog due to the warm currents from the Gulf Stream colliding with the frigid waters of the North Atlantic, and the afternoon of Wednesday, July 25, 1956 was no different. Captain Calamai was armed with the latest radar technology, but he trusted his eyesight most. When he saw the fog thickening he had the ship’s speed slowed from 23 to 21.8 knots to accommodate the loss of visibility. The ship’s watertight doors were closed, the Doria’s foghorn began to blow a six-second long blast every one minute and forty seconds, and a sailor was sent to watch for any approaching ships.

Meanwhile the Stockholm left pier 97 in New York at 11:31 in the morning, cruising away from New York at a speedy eighteen knots. Captain Nordensen was not in charge at the time of the crash, instead Third Officer Johan-Ernst Carstens-Johannsen was overseeing operations on the ship. Carstens-Johannsen did not see any fog at all, and if he had he was under orders to notify the captain immediately. The details of what happened next are hazy: Calamai, seeing something far away on the radar, changed to a more southwestern course to avoid it. Carstens-Johannsen, still not seeing any fog, felt that the ship was drifting north of its prescribed route, into a strong current, so he ordered that the Stockholm’s course be shifted several degrees to the south.

A little before 11:00 p.m., a Doria sailor announced that he could see a ship seventeen miles away. The sailors could tell by the Stockholm’s course that it was moving very quickly and heading directly toward them. Carstens-Johannsen still did not see the Doria, and after another reading informed him that the Stockholm was still running north of its set course, he shifted a few more degrees to the south, a move which should have panicked the Doria’s crew since they could see that in continuing to move to the south the Stockholm was setting itself up for a collision with the Doria. However, the Doria’s radar reading continued to tell its crew that the ships were on course to pass safely starboard-to-starboard.

At 11:00 Captain Nordensen emerged from his cabin on the Stockholm to plot a new course. About five minutes later Carstens-Johannsen saw the Doria on radar. In those days, even the most advanced radar technology was manual and required the user to set the radar to a particular scale. Carstens-Johannsen thought that he was looking at radar data based on a 15-mile range scale, but it is now widely believed that his radar was mistakenly set for 5 miles. So, at this point in the evening, when he saw the Doria on his radar, he believed that she was 12 miles away when actually she was only four miles away.

A little after 11:00 p.m., the Stockholm struck the Doria, delivering a fatal blow. The impact opened such a gaping hole in the Doria’s side that within minutes the ship was leaning dangerously far to her right side — allowing the watertight compartments that kept the ship afloat to flood. For the next several hours, preparations were made to evacuate the Doria, as the Stockholm’s crew worked to assess the damage to their own ship (which did not sink). S.O.S. calls were relayed and multiple ships responded to help rescue the Doria’s passengers and crew. Around 6:00 a.m. after all the survivors had been transplanted onto various rescue ships bound for New York, the Doria’s remaining crew began to disembark — forced to abandoned the beautiful ship. By 9:00 a.m. even Captain Calamai was in a rescue boat. The sinking began at 9:45 a.m. and by 10:00 that morning the Doria was on her side at a right angle to the sea. The Doria fully disappeared from sight at 10:09 — almost exactly eleven hours after the collision with the Stockholm took place.