 It is situated between the two mountains of Mount Kigali and Mount Jali, both of which have elevations of more than above sea level, while the lowest areas of the city have an altitude of .Geologically, Kigali is in a granitic and metasedimentary region, with lateritic soils on the hills and alluvial soils in the valleys.The Nyabarongo River, part of the upper headwaters of the Nile, forms the western and southern borders of the administrative city of Kigali, although this river lies somewhat outside the built-up urban area.