The Sahel means border of margin. It is the largely a semi-arid belt of barren, sandy, and rocky land. This region marks the physical and cultural transition. The Sahel separates the Sahara dessert in the south from the tropical Savannah’s to it’s south. Sahel is located in the semi-arid tropical savannah region whereas Sahara is located in northern part of Africa. The Sahara is the largest hot dessert in the world. It covers the area of 11 countries. Mt. Koussi, an extinct volcano in char is the highest point in Sahara.