Prefab houses are such a hot fad that one could be forgiven for thinking they were just invented. But of course architects have been designing cheap, transportable homes for decades. One of their greatest proponents was none other than Frank Lloyd Wright. In 2007, the Duncan House, one of his 1950s Usonian-style prefabs, was saved from destruction and transported from its original site in Lisle, Illinois, to the Polymath Park Resort, a wooded reserve about 50 miles east of Pittsburgh, in the Laurel Highlands of western Pennsylvania, not far from two other major Wright landmarks.

Now available for overnight stays, making it the ideal base for a weekend Wright tour, this handsome three-bedroom house is a purist's dream. There are Wright-ean gestures galore: public spaces that suggest grandeur, windows meeting at corners to draw the eye out to nature, the massive fireplace that was always the architect's vision of a social hub. Yet this specimen, according to Ron Scherubel, the executive director of the Frank Lloyd Wright Building Conservancy in Chicago, turns out to be "among the cheapest houses Wright ever did."

Wright's passion for prefab started early. In 1916, 10 of his mass-market American System-Built Homes were constructed in Milwaukee. "This is really where his heart was," Scherubel says.

Part of another Wright prefab initiative, the 2,100-square-foot Duncan House was built by the Erdman construction company in 1957 and was designed to be erected with a minimum of fuss and expense. After it arrived at its original 22-acre site in suburban Lisle, southwest of Chicago, concrete blocks were used to build the fireplace and walls. (Unlike the purchasers of other Erdman homes, Donald Duncan, the original owner, didn't want the fancy option package.) These blocks have been replaced at Polymath Park by elaborate stone, reminiscent of Wright's more upscale commissions, which may cause dismay for some connoisseurs. But the ranch-style house, reflecting the mass-market sensibility of the time, remains an extraordinary window into how Wright realized his ideas, no matter what the budget. And, at $425 a night (with a two-night minimum), it's an opportunity not only to examine these ideas up close but to wake up with them as well. (The Duncan House is one of only 11 Wright prefabs still standing and among the very few Wright houses available for accommodation.)

One becomes aware of how deft a move it was for Usonian Preservation, a conservancy group based in nearby Greensburg, to kidnap this populist design — and, in so doing, broaden our understanding of Wright — when visiting Fallingwater, 45 minutes south, near the whitewater-rafting mecca of Ohiopyle. By virtue of its rocky site and absurdly daring design — Wright famously made it hover over a sometimes furious torrent below — the 1935 masterpiece remains an undeniably spiritual experience. What's more exhilarating, once his sheer audacity has been digested, are the relaxed, human dimensions of the interiors. Unlike the Duncan House, where Wright enlarged the scale to give the prefab a touch of grandeur, here he chose relatively low ceilings. It's a counterintuitive decision that forces the eye to travel outside to the floating terraces and woods beyond, while ensuring that the rooms remain eminently habitable, even cozy, albeit in an eccentric way.