Cocoanut Grove fire
1942 CE.
Shown on the map at 42.350°, -71.068°.
The Cocoanut Grove fire was a nightclub fire in Boston, Massachusetts, US on November 28, 1942, which resulted in the deaths of 492 people. It is the deadliest nightclub fire in history and the third-deadliest single-building fire in the United States (after the September 11 attacks and Iroquois Theatre fire). The Cocoanut Grove was one of Boston's most popular nightspots, attracting many celebrity visitors. It was owned by Barnet "Barney" Welansky, who was closely connected to the Mafia and Mayor Maurice J. Tobin. Fire regulations had been flouted; some exit doors had been locked to prevent unauthorized entry, and the elaborate palm tree décor contained flammable materials. The air conditioning system was filled with a flammable gas because of the wartime shortage of nonflammable Freon. During the first Thanksgiving weekend since the U.S. had entered World War II, the Grove was filled to more than twice its legal capacity. The initial source of ignition is not definitely known, but the fire was accelerated by methyl chloride venting from the air conditioning unit.
Text from the Wikipedia article Cocoanut Grove fire, licensed CC BY-SA 4.0.