Précontinent II is the last visible reminder of a series of three French underwater habitats built between 1962 and 1965. Developed by the world-famous oceanography pioneer Jacques-Yves Cousteau, the underwater “village” was supposed to be proof that it’s possible for humans to live underwater without interruption for extended periods of time, at increasing depths.

The habitats were also built to explore the underwater world and conduct research for the petrol industry which financed the project. The project was named précontinent for the French word for continental shelf, the edges of a continent that are covered by ocean.

Précontinent I was the word’s first underwater habitat, located in the Balearic Sea off coast from Marseille. It was completed in September 1962, two years before the American Sealab project. Two aquanauts, Albert Falco and Claude Wesly, lived in the habitat, a five-meter steel cylinder known as “Diogenes.” The habitat was fixed 11 meters under the surface of the water and fed with compressed air. Hot water came through a plastic pipe from a ship, and food in waterproofed containers.

Other  “furnishings” included infrared lamps used as heaters, a record player, a radio, three telephones, a video surveillance system, a library, a TV and a bed. In the bottom of the habitat was an airlock, which allowed the two men to exit into the ocean, where they built compounds for fish and studied their behavior, and took measurements for topographical underwater maps.

A year later, Précontinent II was launched about 35 km northeast, near the Sha’ab Rumi (Arabian for “Roman Reef”), off the coast of Port Sudan. The so-called Starfish House lasted for four weeks, housing a group of oceanographers as well as Madame Cousteau and the parrot Claude, who was supposed to warn the aquanauts of possible danger in the air.

A second Précontinent II habitat, the “Deep Cabin”—a smaller version of the one used in Précontinent I—was installed even deeper into the sea, at 27 meters under the surface. Other structures were built including a tool shed and an air-filled hangar containing the Hydrojet Saucer DS-2, a small submarine for two people, which was equipped with three movable outside lamps, two cameras, a radio, a tape recorder and a movable grappler.