Three main features shape North Africa’s land: the Sahara desert, the Atlas Mountains, and the Nile River. The Atlas Mountains run across Morocco, Algeria, and Tunisia. They are high, rocky ranges with the tallest peaks in the High Atlas of Morocco.
South of the mountains lies the Sahara, the world’s largest hot desert. It has seas of sand called ergs, flat rocky areas called hammada, and stony plains called reg. The desert also has wadis, which are dry riverbeds that fill with water in rainy seasons. In the east, the Nile River cuts a narrow, green valley through Egypt, where most people live and grow crops.