In 2010, the French artist Prune Nourry photographed a friend who was eight months pregnant lying in a bath of warm milk, à la Cleopatra. She used a camping stove, an inflatable pool, and a ladder to set up the shot in the middle of her studio. Four years ago, Château La Coste, a wine estate that covers 500 acres near Aix-en-Provence, approached Nourry to create a permanent installation for its outdoor-architecture trail. That pregnant woman in a pool—seven rounded forms emerging from milk—immediately came to mind. For this assignment, she would bring the bathing body into a whole new dimension and scale. Now it is 90 feet long, reclines in the earth, and one can enter it.

Château La Coste is a “playground of expression” for artists such as Nourry. “They gave me carte blanche,” she says. “It was too beautiful to be true.” For the new work, titled Mater Earth, Nourry chose the location specifically so that the sculpture could be seen from several points of view, including the top of a nearby hill, to embrace the whole work at once. “I wanted the sculpture to look like it has always been there,” she said.

Nourry works on her sculpture.

Visitors enter the belly through a door that’s just four feet high. Once inside, it’s difficult to discern if the surrounding matter is stalagmites or roots or organs. Disorientation, a sense of wonder, is the point. The cavernous space is a cool, dark reprieve from the sun. Light beams in from the belly button overhead, made from a 440-pound piece of cast glass, complete with the imperfect bubbles that formed as part of the pouring process. “It’s like when you look at an embryo and see all the mitochondria,” Nourry says, “and it looks like the Milky Way.” More parallels between the body and the universe.

Human birth and myths of creation are themes that have shaped Nourry as an artist. “It’s repeated into every facet of my work.” Her early projects dealt with subjects such as in-vitro fertilization and sperm banking. With regards to procreation, she likes to maintain the element of mystery. Women have given birth for hundreds of thousands of years, she says, yet “each time it happens, there’s something magical about it.”

For Mater Earth, Nourry collaborated with 80 engineers, architects, and craftspeople to think up original uses of sustainable materials. They forged a combination of stone foundations, adobe bricks, and earth concrete, a mix of recycled materials and earth that took years of research to devise.

The making of Mater Earth.

Mater Earth also incorporates ash, similar to the way Romans used it to protect structures from the rain. Last summer, after a series of fires in southern France, Nourry and her team gathered hundreds of pounds of debris, which they mixed into the final coating of the sculpture. Says Nourry, “After the destruction, we wanted to use it for creation.”

Serendipitously, at the time that Nourry was choosing where to locate Mater Earth, she was pregnant with her son. He was the first person, aside from the craftspeople, to enter the sculpture once it was completed. “That synchronicity was very special,” Nourry says. The symbolism doesn’t end there. “The process itself was a kind of pregnancy because construction lasted for nine months, and it was very hard to get off the ground.” —Nadine Zylberberg

Mater Earth is on at Château La Coste, in Aix-en-Provence, France

Nadine Zylberberg is a New York–based writer and editor