Matmata's houses are dug into old dust. Saharan storms spent millennia laying fine windblown silt over these limestone hills, and it makes an ideal building material: soft enough to cut with hand tools, firm enough to stand in vertical walls and hold a ceiling without a single beam — which mattered, because the treeless plateau had no timber to offer. Berber families sank a circular courtyard into it, up to fifteen metres across and ten deep, then tunnelled rooms sideways out of the pit walls, with grain lofts above and, in bigger houses, passages linking one pit to the next. What they built is a thermal machine. In July, when the plateau bakes at 33°C, the rooms hold 23-25°C; in January, when the night outside falls to about 4°C, they stay near 15°C. Underground, the difference between summer and winter nearly disappears. The village also disappears from view: from a few hundred metres off there is no roofline, no wall — only an ochre plain punched with holes.
Walk down the ramp into a courtyard and the cool arrives before your eyes adjust. Rooms open off a well of sky — a cooking hollow blackened by generations of smoke, a shelf of clay jars left standing where the household set them down. The most visited pit belongs to the Hotel Sidi Driss, where the interior of Luke Skywalker's home was filmed in 1976 and again a quarter-century later. Matmata's hard chapter came in 1969, when weeks of rain brought pit-houses down; a delegation went to Gabès for help, the authorities put up a surface settlement, and most families dug their homes out and stayed underground. Since then, work and schools have pulled people down to Nouvelle Matmata on the plain, and the old village now lives largely on visitors — pits reopened as guesthouses, cafés and show-homes. A minority are still simply homes.