Setting the scene
Edgar Kaufmann Sr., a Pittsburgh department-store owner, owned Bear Run property in Pennsylvania's Laurel Highlands where his family picnicked. He hired Frank Lloyd Wright to design a weekend house integrated with a waterfall.
What happened
Fallingwater was completed in 1939 with reinforced concrete terraces cantilevered over the stream, using local sandstone and glass walls that blur indoors and outdoors. Wright was 72 and had thought the commission lost to younger architects.
Why it still matters
The house is now a UNESCO World Heritage Site and museum managed by the Western Pennsylvania Conservancy. Memorable detail: Kaufmann expected the house to sit downstream with a view of the falls; Wright instead anchored the living room directly above the cascade, so water roars beneath the floor.
Background
The Kaufmann residence became an architecture pilgrimage.