Liberia the Cestos River, all of which flow into the Atlantic. The Cavalla is the longest river in the nation at . The highest point wholly within Liberia is Mount Wuteve at above sea level in the northwestern Liberia range of the West Africa Mountains and the Guinea Highlands. However, Mount Nimba near Yekepa, is higher at above sea level but is not wholly within Liberia as Nimba shares a border with Guinea and Ivory Coast and is their tallest mountain as well. Forests on the coastline are composed mostly of salt-tolerant mangrove trees, while the more sparsely populated inland has
West Africa this land is plains lying less than 300 meters above sea level, though isolated high points exist in numerous states along the southern shore of West Africa. The northern section of West Africa (narrowly defined to exclude the western Maghreb) is composed of semi-arid terrain known as Sahel, a transitional zone between the Sahara and the savannahs of the western Sudan. Forests form a belt between the savannas and the southern coast, ranging from 160 km to 240 km in width. The northwest African region of Mauritania periodically suffers country-wide plagues of locusts which consume water, salt and crops on