The Libyan Desert forms the northern and eastern part of the Sahara Desert and covers an area of approximately 1,100,000 square kilometers (420,000 sq mi). The desert extends approximately 1,100 km from east to west, and 1,000 km from north to south, in about the shape of a rectangle. The Libyan Desert covers eastern Libya, western Egypt, and northwestern Sudan. Like most of the Sahara Desert, this desert is primarily sand and hamada or stony plain. The Libyan Desert is one of the harshest parts of the bigger Sahara Desert. This is one of the sunniest and driest places on Earth; many decades may easily pass without seeing any rainfall at all and the sky is always cloudless, clear, and luminous. Extreme heat and extreme dryness both contribute to one of the highest levels of aridity found in the planet.
Sand plains, dunes, ridges, and some depressions (basins) typify the endorheic region, with no rivers draining into or out of the desert. The Gilf Kebir plateau reaches an altitude of just over 1,000 m, and along with the nearby massif of Jebel Uweinatis an exception to the uninterrupted territory of basement rocks covered by layers of horizontally bedded sediments, forming a massive sand plain, low plateaus, and dunes.https://en.wikipedia.org/wiki/Libyan_Desert