This Letter communicates the discovery of an exceptionally large, double-ringed crater in the eastern part of the Great Sahara, North Africa. The crater is centred at 24.40° N 24.58° E, straddling the boarder between Egypt and Libya. It is the 15th and largest impact crater identified in the Sahara. Landsat Enhanced Thematic Mapper Plus (ETM+) images as well as Radarsat-1 data reveal a discontinuous outer rim, 31 km in diameter, and a group of prominences forming an inner ring. The Nubian sandstone surface in which the crater was formed has undergone severe erosion. Thus, the crater morphology was affected by both aeolian and fluvial processes. Courses of a major river and smaller streams, now dry, have eroded much of the crater's outer rim as revealed by Shuttle Radar Topography Mission (SRTM) data. The probable impact that created the crater, named Kebira, meaning large in Arabic, is possibly the source of the silica glass fragments that abound on the desert surface between giant linear dunes of the Great Sand Sea in southwestern Egypt.