Sahara Desert
The Sahara is the largest hot desert in the world, stretching across North Africa and covering an area roughly the size of the United States.
Just a few thousand years ago, the region now defined by relentless heat and shifting sand was a green savanna dotted with lakes — a reminder of how quickly climate can reshape a landscape.
A Vast and Varied Landscape
The Sahara spans approximately 3.6 million square miles across 11 countries in North Africa. Contrary to the popular image of endless sand dunes, much of the Sahara is actually composed of rocky plateaus, gravel plains, and mountain ranges, with sand seas known as ergs making up only about a quarter of its total area.
A Once-Green Landscape
Remarkably, the Sahara was not always a desert. As recently as 5,000 to 10,000 years ago, during a period known as the African Humid Period, the region was a green savanna dotted with lakes and abundant wildlife, before a gradual shift in Earth's orbital patterns brought the drier conditions that define the region today.
Extreme Conditions
The Sahara experiences some of the most extreme temperature swings on Earth, with daytime temperatures regularly exceeding 120°F (49°C) in summer, while nighttime temperatures in some areas can drop below freezing due to the lack of humidity to retain heat.
A Homeland, Not an Empty Space
Despite its harsh conditions, millions of people live in and around the Sahara, including nomadic groups such as the Tuareg, who have developed sophisticated cultural and survival practices adapted to desert life over many centuries, and continue to traverse ancient trans-Saharan trade routes to this day.
