Fallingwater, one of Frank Lloyd Wright's most widely-acclaimed works, was designed in 1935 for the family of Pittsburgh department store owner Edgar J. Kaufmann. Construction of the house began in 1936, and the house's acclaim has grown steadily since that time. The key to the setting of the house is the waterfall over which it is built. Historically, the falls wer a focal point of Kaufmanns' activities, and the family indicated to Wright their desire to locate their weekend house near them. Much to their surprise, Wright designed the house to rise above the waterfall, rather than face it. the kaufmanns adopted Wright's original scheme with few changes. Perhaps better than any single work, Fallingwater exemplifies Wright's concept of organic architecture: the harmonious union of art and nature. Completed with a guest and service wing in 1939, Fallingwater was constructed of sandstone quarried on the property, and was laid by local craftsman. the stone serves to separate reinforced concrete "trays" dramatically cantilevered over the stream. Fallingwater was the weekend home of the Kaufmann family from 1937-1963, when Edgar Kaufmann, Jr. entrusted the house, its contents, and the grounds to the Western Pennsylvania Conservancy. Fallingwater is the only major Wright work to come into the public domain with its setting, original furnishings, and artwork intact.