On this day, June 15, in 1904, more than 1,000 people died when the steamboat General Slocum caught fire in the East River in New York. The boat was a paddle steamer built in 1891. At the time of the 1904 fire, the ship was on a chartered run and was carrying about 1,300 members of St. Mark’s Evangelical Lutheran Church to a picnic on Long Island.

An estimated 1,021 people died in the fire, making the blaze New York City’s deadliest disaster until the Sept. 11, 2001, terrorist attacks.