On May 31, 1889, a dam above Johnstown, Pennsylvania, failed after days of heavy rain, releasing a massive wall of water into the valley below. The flood destroyed much of the town and killed more than 2,000 people. Many structures were swept away or crushed, and fires broke out among the debris. Investigations later criticized the private owners of the dam for inadequate maintenance and safety measures. The disaster drew national attention and led to extensive relief efforts by groups such as the American Red Cross. The Johnstown Flood remains one of the deadliest and most studied disasters in U.S. history.
