The Middle Atlas is a mountain range in Morocco. It is part of the Atlas mountain range, a mountainous region with more than 100,000 km², 15 percent of its landmass, rising above 2,000 metres. The Middle Atlas is the northernmost and second highest of three main Atlas Mountains chains of Morocco. To south, separated by the Moulouya and Um Er-Rbiâ rivers, lies the High Atlas. The Middle Atlas form the westernmost end of a large plateaued basin extending eastward into Algeria, also bounded by the Tell Atlas to the north and the Saharan Atlas to the south, both lying largely in Algeria. North of the Middle Atlas and separated by the Sebou River, lie the Rif mountains which are an extension of the Baetic System, which includes the Sierra Nevada in the south of Spain. The basin of the Sebou is not only the primary transportation route between Atlantic Morocco and Mediterranean Morocco but is an area, watered by the Middle Atlas range, that constitutes the principal agricultural region of the country.