The communities, which date to between about A.D. 1 and 500, belonged to an advanced but mysterious people called the Garamantes, who ruled from roughly the second century B.C. to the seventh century A.D.

Researchers uncovered the Garamantes' walled towns, villages, and farms after poring over modern satellite images—including high-resolution pictures used by the oil industry—as well as aerial photos taken during the 1950s and 1960s. (See pictures of Libya's remote Sahara.)