It started with the snow. Having fled England to forge a new life in the Mexican jungle, Edward James devoted years to cultivating tens of thousands of orchids there, only to return from a 1962 trip to New York to discover that they had perished in a freak snowstorm. So rare was snow in that part of Mexico that the local people did not know what it was and explained the devastation thus: “Oh, Don Eduardo, white ashes fell and burned everything!”

James, who had inherited a fortune from his father, an American railroad and mining magnate, decided to replace the orchids with something the weather could not destroy. For 20 years, he dedicated much of his time and wealth to the design and construction of a spectacular series of concrete sculptures amid the luscious vegetation of Las Pozas, his vast estate in a tropical rain forest high in the Sierra Madre Oriental mountains near the tiny town of Xilitla, about an eight-hour drive north of Mexico City.

Some of the sculptures were inspired by the shapes of exotic plants and trees in the surrounding jungle; others, by the convoluted forms in the immense collection of works by the surrealist artists James had assembled back in England. Among his fantastical structures were totem poles, hidden rooms, teetering towers, and staircases leading to nowhere. James gave them baffling names like The House With Three Storeys That Could Be Five and Temple of the Ducks and instructed the hundreds of artisans who’d worked for him over the years to leave many of them unfinished. A 1978 British television documentary filmed him strolling beatifically around his domain: He was big-bellied beneath a poncho, had an unkempt white beard, and green parrots were perched on his shoulders.

After James’s death, in 1984, Las Pozas was cared for by the family of Plutarco Gastelum, who had befriended him 40 years before, when Gastelum was the handsome young manager of a telegraph office in Cuernavaca. Having helped James find Las Pozas in 1947, Gastelum worked there as foreman on the creation of both the orchid garden and the concrete follies. He married a local woman and they had four children, who called James Uncle Eduardo. James eventually adopted the children, but his will did not provide for the estate’s upkeep, and the Gastelums could not afford to maintain it. The carefully cultivated plants died, the animals in the menagerie had to be released into the jungle, and the sculptures were soon overgrown with foliage.

A few dedicated surrealist fans continued to make the tortuous journey through the mountains to Las Pozas each year, but the stories of the follies built by an eccentric multimillionaire in so beautiful and far-flung a place seemed increasingly apocryphal. In 2007, the estate was acquired by Fondo Xilitla, a charitable foundation formed to run it and to restore James’s sculptures. Since then, what James called his Surrealist Xanadu has become a little more accessible.

The photographer Tim Walker first heard of Las Pozas from a friend, the Irish model Jasmine Guinness, James’s goddaughter. When the art director Jerry Stafford, who has long been fascinated by James, suggested that they go there to shoot Tilda Swinton for W, Walker looked for ways to include references to James’s earlier life in England and his art collection in the photographs. Most extraordinary of all are the glimpses of James’s concrete fantasies amid the opulent greenery of Las Pozas. “I hadn’t realized how big it was—and how incredibly ambitious it had been of James to create another world somewhere so remote, where there was nothing and where nature can be so destructive,” Walker says. “It’s the power of the dreamer.”