The largest hot desert in the world is the Sahara Desert. Spanning approximately 9.2 million square kilometers (3.6 million square miles), the Sahara covers parts of several North African countries, including Algeria, Sudan, Libya, and Mali. It is characterized by its vast expanses of sand dunes, rocky plateaus, and extreme temperatures, with daytime highs often exceeding 50 degrees Celsius (122 degrees Fahrenheit). Despite the harsh conditions, the Sahara's ecosystem supports a variety of flora and fauna adapted to arid environments. The desert plays a vital role in regional climate and has significant cultural and historical importance.