In western Bolivia, the Cordillera Occidental is a chain of dormant volcanoes and solfataras, volcanic vents emitting sulfurous gases. Bolivia's highest peak, the snowcapped Nevado Sajama , is located here. The entire cordillera is of volcanic origin and an extension of the volcanic region found in southern Peru. Most of the northern part of this range has an elevation of about ; the southern part is somewhat lower. Rainfall, although scanty everywhere, is greater in the northern half, where the land is covered with scrub vegetation. The southern area receives almost no precipitation, and the landscape consists mostly of barren rocks. All of the Cordillera Occidental regions are sparsely populated, and the south is virtually uninhabited.