The Kilimanjaro volcano last showed signs of major activity in the Pleistocene era, (about 4 million years ago). It is not only the highest mountain in Africa, rising 4,877m above the surrounding plains to 5895m, but also one of the largest volcanoes in the world, covering an area of some 388,500 hectares. The mountain has three main peaks of varying ages with clusters of small cones around the base.Kibo, the highest and most recently formed peak still show signs of minor activity in the centre. It consists of a crater within a crater with an ash pit in the centre.
Uhuru Peak is on the southern rim of the outer crater, the sides of which are 2 kms apart. Kibo still retains permanent ice and snow, although the area covered is rapidly diminishing, with one glacier extending as low as 4500m. The oldest peak, Shira, rises to 3962m, with only the western and southern rims remaining. The remains of the northern and eastern rims are covered by later materials that have erupted from Kibo. This has led to the formation of the relatively flat Shira Plateau which covers 6200 hectares between the two peaks.
The rugged Mawenzi peak at a height of 5149m lies to the east. It’s erosion-carved form has a steep 1000m eastern face with a complex series of gullies and rock faces, rising above two deep gorges, the Greater Barranco and Lesser Barranco. Linking Mawenzi to Kibo is The Saddle a vast plateau that forms the largest area of high-altitude tundra in tropical Africa