The Western Desert is a desert region West of the Nile in Egypt, extending to Libya. In most of Upper Egypt, the desert encroaches very near the Nile, with a flood plain only a few kilometers wide.

It contains the Great Sand Sea and several oases, including Siwa, Farafra, Baharia, Dakhla, and Kharga. Due to erosion of the underlying sedimentary rock, naturally occuring pyramidal structures have formed in some locations.