Photo © Roland Halbe

The aptly named Truffle House sits on Spain’s northwestern Costa da Morte (the Death Coast) in a small fishing village. Madrid-based Ensamble Studio chose the site for an experimental project “to let nature take part in the architectural process,” according to principal Antón García-Abril. The adventurous team dug a hole in the ground, piling topsoil around the perimeter. They built a hay bale structure, covered it with concrete, and buried the entire mound in soil. After several months, they excavated the mass to reveal what was essentially a man-made stone. Respecting the rural surroundings, the team then encouraged a local calf named Paulina to munch her way through the hay over the course of one year, revealing the architectural condition. The raw interior of the weekend retreat has just enough room for one bed, simple plumbing, and even a fireplace. The house was inspired by Le Corbusier’s Cabanon: “This has the same program, the same scale,” says García-Abril. “It’s our Cabanon of béton [concrete].”