The Sahara is built up of a diverse amount of geographic landscapes, comprising mainly of sand dunes, gravel plains, rocky plateaus, and even some mountain ranges, such as the Ahaggar (with peaks rising above 9,500 feet) and Tibesti ranges (containing Mount Emi Koussi, a peak that rises a lofty 11,204 feet). Its iconic sand dunes, particularly in Algeria and Libya, can reach heights of up to 180 meters!