Ethiopia is bordered by Eritrea to the north, Djibouti to the northeast, Somalia to the east, Kenya to the south, and South Sudan and Sudan to the west.

Ethiopia’s topography is characterized by four geologic formations. The oldest basal complex, dating back more than 540 million years, is made up of rocks of Precambrian origin, similar to the rest of Africa. In some parts of northern, western, and southern Ethiopia, exposed rock layers of granite and schist can be found, while the Precambrian layer is buried under more recent geologic formations elsewhere. Sedimentary layers of limestone and sandstone from the Mesozoic Era can be found in certain areas, although most have either eroded or been covered by volcanic rocks. Younger sedimentary layers are present in the northern part of the country and in the Rift Valley. Basaltic layers from the Cenozoic Era now cover two-thirds of Ethiopia’s land surface, with thickness ranging from about 1,000 feet to almost 10,000 feet. The Rift Valley, a massive tectonic trough, runs through the middle of the country from the northern frontier with Eritrea to the southern border with Kenya.

Ethiopia’s complex relief can be classified into five topographic features: the Western Highlands, the Western Lowlands, the Eastern Highlands, the Eastern Lowlands, and the Rift Valley. The Western Highlands are the most extensive and rugged component, with the North Central massifs being the most spectacular. These massifs have elevations ranging from 14,872 feet for Mount Ras Dejen, the highest point in Ethiopia, to the Blue Nile and Tekeze river channels 10,000 feet below. Lake Tana, the largest inland lake in Ethiopia and the main reservoir for the Blue Nile River, is located in this region at an elevation of about 6,000 feet.

The Western Lowlands stretch along the border with Sudan and South Sudan and include the lower valleys of the Blue Nile, Tekeze, and Baro rivers. With elevations of about 3,300 feet, these lowlands become too hot for dense settlement.

The Rift Valley is part of the larger East African Rift System and is hemmed in by the escarpments of the Western and Eastern Highlands. It has two distinct sections: a northeast section that widens into a funnel shape as it approaches the Red Sea and the Gulf of Aden, and a southwest section that is a narrow depression containing Ethiopia’s Lakes Region. The northeastern section has high temperatures and lack of moisture, making it unattractive for settlement. The southwestern section, on the other hand, is a productive and settled part of Ethiopia, with the Lakes Region being an internal drainage basin for many small rivers.

The Eastern Highlands, although smaller in extent than the Western Highlands, offer equally impressive contrast in topography. The highest peaks are Tullu Deemtu and Mount Batu. The Eastern Lowlands, resembling a bridal gown train, gently roll from the narrow band of the Eastern Highlands to the Somalian border. The Shebele and Genale rivers cross the lowlands, moderating the desert ecology.