The Atlas Mountains are a mountain range in northwest Africa extending about 2400 km through Morocco, Algeria, and Tunisia, and including The Rock of Gibraltar. The highest peak is Toubkal, with an elevation of 4167 m, located at in southwestern Morocco. The Atlas ranges separate the Mediterranean and Atlantic coastlines from the Sahara Desert. The population of the Atlas mountains are mainly Berber in Morocco and mainly Arab in Algeria.

Because North America, Europe and Africa were connected eons ago, the Atlas mountains are believed to have originally been formed as part of Alleghenian orogeny . These mountains were formed when Africa and America collided, and were once a chain far higher than today's Himalaya. Today, the remains of this chain can be seen in the Fall line in the eastern United States. Some remnants can also be found in the later formed Appalachians in North America. The Sierra Nevada mountains in Spain were likewise formed in this continental collision.

The mountains are divided into the Grand Atlas of Morroco, the lower Tell Atlas running near the coast and the larger Saharan Atlas running further south.