7: The Sacred Sahara Desert

Tonight, you'll be whisked off to the sacred Sahara Desert the largest desert in the world. The Sahara is one of the harshest environments on Earth, covering 3.6 million square miles, nearly a third of the African continent, about the size of the United States (including Alaska and Hawaii). The name of the desert comes from the Arabic word ṣaḥrāʾ, which means "desert."