But one spring night in 1889 and on into the next day, drenching thunderstorms pounded the mountainsides.

The lake rose, intensifying pressure against the dam.

With the force of a giant waterfall, the dam burst, launching a wall of water 18 meters [60 feet] high down the funnel toward Johnstown faster than warnings could be sounded.

Grinding up trees, houses, boulders, locomotives, humans, and animals in its path, it slammed into Johnstown, pulverizing the center of town.

Afterward, most observers blamed the rich yachtsmen and their leaky earthen dam for the deaths of 2,200 men, women and children.

Lost in Scotland, Flickr Creative CommonsJohnstown is still flood-prone. This shot was taken in 1977, when 85 people died, hundreds were left homeless, and property damage topped $300 million in flooding that followed a summer deluge.

These days, tourists make a point of visiting a museum that tells the dramatic story. Ironically, it's located in a building donated by industrialist Andrew Carnegie.

He was one of the owners of the pleasure club whose members cavorted high above ill-fated Johnstown, Pennsylvania.