What killed over 2,000 people in Johnstown, Pennsylvania in 1889?

The Johnstown Flood occurred on May 31, 1889, after the catastrophic failure of the South Fork Dam on the Little Conemaugh River 14 miles (23 km) upstream of the town of Johnstown, Pennsylvania. The dam broke after several days of extremely heavy rainfall, releasing 14.55 million cubic meters of water  (16 million US tons) from the reservoir known as Lake Conemaugh.

The total death toll was 2,209, making the disaster the largest loss of civilian life in the United States at the time (perhaps with exception of the Peshtigo Fire). Ninety-nine entire families died in the flood, including 396 children. One hundred twenty-four women and 198 men were widowed, 98 children were orphaned. One-third of the dead, 777 people, were never identified; their remains were buried in the "Plot of the Unknown" in Grandview Cemetery in Westmont, PA.

At Point Park in Johnstown, at the confluence of the Stonycreek and Little Conemaugh rivers, an eternal flame burns in memory of the flood victims.

The Carnegie Library is now owned by the Johnstown Historical Society, which has adapted it for use as The Flood Museum.

Portions of the Stone Bridge have been made part of the Johnstown Flood National Memorial, established in 1969 and managed by the National Park Service.

The flood has been the subject or setting for numerous histories, novels, and other works as well.