The house has long been an expensive proposition. Set on nearly an acre in the Los Feliz neighborhood of L.A., the home -- three bedrooms and three and half baths, plus staff quarters that push the listing to 6,000 square feet -- cost $300,000 to build, about $3.8 million today, adjusted for inflation.

Wright's client was Charles Ennis, the owner of a men's clothing store in downtown L.A. and an enthusiast of Mayan art and architecture. For each of Wright's houses built with concrete blocks, or textile blocks as they are often called, Wright designed a custom pattern. For the Ennis house, the pattern was a Greek key. Within the interlocking form, it's possible to interpret a stylized "g" -- perhaps an allusion to the Masonic Order, of which Ennis was a member, and the organization's symbol, the compass with the letter "g" in the middle representing God.

Wright had used concrete in monumental projects, but in the 1920s it was still considered a new material, especially for home construction. The concrete was a combination of gravel, granite and sand from the site, mixed with water and then hand-cast in aluminum molds to create a block 16 inches wide, 16 inches tall and 3 1/2 inches thick. It took 10 days for each block to dry before it could be stacked into position. The double-wall construction called for exterior blocks and interior blocks to be set about 1 inch apart, and estimates of the total number of blocks deployed by Wright have ranged from 27,000 to 40,000.

It was an experiment in the functional and artistic possibilities of concrete, which Wright believed held potential as a material for affordable housing. The phrase "textile block" came from the way vertical and horizontal steel rods were woven through channels in the concrete, a technique that was supposed to keep the blocks knitted together and held in position. The net visual effect was nothing short of monumental.

But although the Ennis house was grand in scale and historic in sweep, it remained "highly livable," said Janet Tani, whose father, Augustus O. Brown, owned the property from 1968 to 1980.

"One gets to experience the changes of light throughout the day and how that impacts interior spaces on a large scale," Tani said.

She noted how one side of the house seems to hover above a growing metropolis, while the other side points toward Griffith Park's undeveloped hills and land "that looks like it must have looked 500 years ago," she said. "By walking a few feet, one can be in a completely different environment."

Karrie Jacobs, an architecture columnist and the founding editor of Dwell magazine, remembered visiting the Ennis house in 2005, sitting at the dining table and watching hawks circle over L.A. She said it's her favorite Wright house, partly because it represents an evolution from the beginning of Wright's career, when the architect "was still a 19th century Midwesterner." His early Prairie Style houses tended to hunker down, low and dark.

"By the time he designed the Ennis house in 1923, he'd lived and worked in Tokyo and built several houses in L.A.," Jacobs said. "He was more cosmopolitan and less afraid of sunlight. And Ennis is strangely, monumentally, vertical, with its double- or triple-height rooms. Usually, in Wright houses, I feel a little claustrophobic, a little trapped in the man's tightly choreographed conception of domestic life. But during my one visit to Ennis, I felt as if I was in a different world, someplace I'd never been before -- and maybe someplace Wright had never been before, either."

The house, Jacobs said, doesn't fit neatly into Wright's oeuvre or any other architectural timeline. "I think of it, affectionately, as Wright's San Simeon," she said.

Residents included John Nesbitt, known for his radio and film series "The Passing Parade," who owned the house from 1940 to 1942. He had Wright design a 20-by-40-foot swimming pool and convert a storage area off the entry into a billiard room with a fireplace. These 1940 additions also included Wright's plans for furniture, window treatments and rugs.

In his drawings for Nesbitt, Wright renamed the house Sijistan, after a 10th century Persian palace. Although none of the furniture was built, several chairs were later produced for an owner of Wright's Storer house, another textile block design.

Tani's father was the last private owner of the Ennis house. To ensure its safe keeping, Brown created the Trust for Preservation of Cultural Heritage, now the Ennis House Foundation. The home sustained serious damage in the 1994 Northridge earthquake, then was briefly red-tagged after the torrential rains of 2004. The next year, the National Trust for Historic Preservation designated the Ennis house as one of the most endangered landmarks in the country. The Ennis House Foundation has stabilized a buckling retaining wall and made other repairs, but a significant investment in restoration will be required before the house can be the grand residence it once was.

Tani recalled how the house always managed to make visitors marvel.

"Shortly after we moved into the house, I came home from school one day and saw Edmund Teske standing outside on the sidewalk looking at the house," she said, referring to the photographer known for his work with Wright. "I went inside and told my mother about Teske's presence. She told me to go outside and invite him in, which I did. He was absolutely thrilled."

Wright likely would have been thrilled, too. In 2009, 50 years after his grandfather's death, Eric Lloyd Wright announced that the Ennis House Foundation was putting the landmark up for sale. A private owner, he said, would be better able to preserve Frank Lloyd Wright's legacy.

"My grandfather designed homes to be occupied by people," his statement to The Times said. "His homes are works of art. He created the space, but the space becomes a creative force and uplifts when it is lived in every day."

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