Why are Morocco, Algeria, and Tunisia sometimes called the Atlas Lands?

Morocco, Algeria, and Tunisia are referred to as the Atlas Lands because the Atlas Mountains dominate their northern landscapes.1

This series of mountain ranges extends for more than 1,200 miles (2,000 kilometers) across these three countries, stretching from Agadir, Morocco, in the southwest to Tunis, Tunisia, in the northeast. The mountains serve as a significant geographic feature, forming a high barrier that separates the Mediterranean basin to the north from the Sahara to the south. While these countries also contain sizable sections of the Sahara, the well-watered mountains provide the foundation for the livelihood of most of the region's inhabitants.231