Aïr massif, French Massif De L'aïr, group of granitic mountains rising sharply from the Sahara in central Niger. Several of these mountains approach and exceed 6,000 feet (1,800 m), the highest being Mount Gréboun (6,378 feet [1,944 m]). The mountains are dissected by deep valleys, called koris, in which some vegetation permits the pasturage of livestock, owned mainly by Tuaregs. Hot springs are found in the mountains, as are ancient rock carvings. Uranium and other minerals are mined.