Kavir-e Namak or the Great Salt Desert is a large desert lying in the middle of the Iranian plateau. It is about 800 kilometers long and 320 kilometers wide with a total surface area of about 77,600 square kilometers, making it the Earth's 23rd largest desert. The area of this desert stretches from the Alborz mountain range in the north-west to the Dasht-e Lut ("Emptiness Desert") in the south-east and is partitioned between the Iranian provinces of Khorasan, Semnan, Tehran, Isfahan and Yazd. It is named after the salt marshes (kavirs) located there. The desert is almost uninhabited.