"We clocked over 500 people coming through our neighborhood," Adriene Biondo said recently. "We had vintage cars cruising up and down the street that day. People were tuned into the oldies station. It was a really exciting moment." Biondo, a short, roundish 49-year-old with the breathy voice of a chanteuse, was talking about the 2000 "How Modern Was My Valley" tour as if it happened yesterday. Sponsored by the Modern Committee, which she heads -- a furiously active branch of the city's dominant preservation organization, the Los Angeles Conservancy -- the tour brought a flood of tourists into the neighborhood. It also focused attention on the architecture about which Biondo is most passionate: the homes, including her own, built by Eichler.

Eichler, who was responsible for the construction of some 11,000 homes, mostly in the San Francisco Bay area, was the last and most successful of a breed now largely extinct. In the years after World War II, commercial home-builders all over the country, but particularly in the West, began experimenting with new methods of construction and new styles of architecture. Abraham Levitt and his sons applied mass-production methods to building thousands of tiny ranch houses and Cape Cods on Long Island. Other developers, trying to remake the American dream, combined ideas from European Modernists -- simple geometric forms, functionalism, flexible space -- with a New World elan....

Each housing development Eichler erected represented a variation on the same program for happy family life. In the Balboa Highlands tract, the clean wood-and-concrete-block facades were designed to conceal the interior from the street. But inside, a whole world opens up: behind the front door of each house is an open-air atrium...