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.
Fallingwater stands as one of Wright's greatest masterpieces both for its dynamism and for its integration with the striking natural surroundings. The extent of Wright's genius in integrating every detail of this design can only be hinted at in photographs. This organically designed private residence was intended to be a nature retreat for its owners. The house is well-known for its connection to the site: it is built on top of an active waterfall which flows beneath the house. The fireplace hearth in the living room is composed of boulders found on the site and upon which the house was built — one set of boulders which was left in place protrudes slightly through the living room floor. Wright had initially intended that these boulders would be cut flush with the floor, but this had been one of the Kaufmann family's favorite sunning spots, so Mr. Kaufmann insisted that it be left as it was. The stone floors are waxed, while the hearth is left plain, giving the impression of dry rocks protruding from a stream.
Integration with the setting extends even to small details. For example, where glass meets stone walls, there is no metal frame; rather, the glass is caulked directly to the stone. There are stairways directly down to the water. And in the "bridge" that connects the main house to the guest and servant building, a natural boulder drips water inside, which is then directed back out. Bedrooms are small, some even with low ceilings, perhaps to encourage people outward toward the open social areas, decks, and outdoors.
The active stream (which can be heard constantly throughout the house), immediate surroundings, and locally quarried stone walls and cantilevered terraces (resembling the nearby rock formations) are meant to be in harmony, in line with Wright's interest in making buildings that were more "organic" and which thus seemed to be more engaged with their surroundings. Although the waterfall can be heard throughout the house, it can't be seen without going outside. The design incorporates broad expanses of windows and the balconies are off main rooms giving a sense of the closeness of the surroundings. The experiential climax of visiting the house is an interior staircase leading down from the living room allowing direct access to the rushing stream beneath the house.
Wright's views of what would be the entry have been argued about; still, the door Wright considered the main door is tucked away in a corner and is rather small. Wright's idea of the grand facade for this house is from the perspective of all the famous pictures of the house, looking up from downstream, viewing the opposite corner from the main door.
On the hillside above the main house is a four-car carport (though the Kaufmanns had requested a garage), servants' quarters, and a guest bedroom. This attached outbuilding was built one year later using the same quality of materials and attention to detail as the main house. Just uphill from it is a small swimming pool, continually fed by a natural water, which then overflows to the river below.