Fallingwater was built for the Kaufmann family of Pittsburgh, well known for the family department store that was an important part of Pittsburgh life. The Kaufmanns were interested in building a weekend retreat and contracted with Wright to design and build it for them. The house was completed in 1937 and it was used by the family into the 1960s. It became a National Historic Landmark in 1976 and is part of a bid to become a World Heritage Site along with nine other Wright buildings.