Chad is located on a wide plain with flanks that rise gently eastward toward the Ennedi Range (ENN) and north toward the Tibesti Mountains, which culminate in the Sahara’s highest peak, Emi Koussi, at 3,415 m. The country’s northern third consists of vast sandy and gravel plains, too dry for cultivation except for small- scale traditional irrigated farming in scattered oasis towns. The high plateaus of the Ennedi and Ouaddaï (OUA) ecoregion gently slope toward the lower Sahelian plains of the Batha (BND and BSD) and Kanem (KAN) ecoregions, stretching to Lake Chad far to the west. The southern third of Chad is in the Sudanian climate region, with many ecoregions that are defined by plateaus and local highlands, expansive plains, and broad drainage channels that flood annually. To the west, these plains are more conducive to agriculture owing to their deep, rich alluvial soils. In contrast, the largest ecoregion in the southeast, Moyen-Chari and Salamat Plain (EMS – Eastern Middle-Chari and Salamat), contains large expanses of Sudanian zone woodlands and savannas where scattered communities are engaged in subsistence farming, fishing, and raising livestock.