Fallingwater house at Bear Run, Pennsylvania. Fallingwater, also known as the Edgar J. Kaufmann Sr. Residence, is a house designed by American architect Frank Lloyd Wright in 1935 in rural southwestern Pennsylvania, 50 miles southeast of Pittsburgh, and is part of the Pittsburgh Metro Area. The house was built partly over a waterfall in Bear Run at Rural Route 1 in the Mill Run section of Stewart Township, Fayette County, Pennsylvania, in the Laurel Highlands of the Allegheny Mountains.