One of the most important features of this region of Africa resulted from faulting and cracking on its eastern side. This has caused the Great Rift Valley, which extends from the Middle East to Mozambique, passing in a north-south direction right through Ethiopia. This shearing of the earth's surface occurred at the same time that the Arabian Peninsula, geologically a part of Africa, was sundered from the rest of the continent. Volcanic activity, which has continued until today, finds expression in volcanoes in Ethiopia's Danakil Depression, as well as in the hot springs in many parts of the country.

Earth tremors are often felt, and exposed cones of old volcanic plugs are seen throughout the plateau. After the Rift opened, much of this area was flooded by the inrushing waters of the red Sea, a flood that was subsequently stemmed by fresh volcanic activity that raised barriers of basaltic lava. Behind these barriers the trapped inland sea that had formed began to evaporate under the fierce heat of the tropical sun - a process that is almost complete today. Only a few scattered, highly saline lakes - Gamarri, Affambo, Bario, and Abbe remain. Elsewhere, there are huge beds of natural salt - which, at points, are calculated to be several thousands of metres thick.

Covering an area of 2,162 square kilometers on the banks of Omo River, the Mago National Park is relatively undeveloped for tourists. The broad grasslands teem with herds of Buffalo, Giraffe, Elephant and Kudu, while sometimes it is possible to find Lion, Leopard and Burchell's Zebra.

The park rises in the north to mount Mago (2,528 meters) and is home to 56 species of mammals. Mago National Park mainly grass savannah, with some forested areas around the rivers. Very dense bush makes for difficult game viewing. The Birds are typical of the dry grassland habitat, featuring bustards, hornbills, weavers, and starlings. Kingfishers and herons can be seen around the Neri River, which provides an alternative habitat.

Known locally as Tis Isat - 'Smoke of Fire' the Blue Nile Falls is the most dramatic spectacle on either the White or the Blue Nile rivers. Four hundred meters (1,312 feet) wide when in flood, and dropping over a sheer chasm more than forty-five meters (150 Feet) deep the falls throw up a continuous spray of water, which drenches onlookers up to a kilometer away. This misty deluge produces rainbows, shimmering across the gorge, and a small perennial rainforest of lush green vegetation, to the delight of the many monkeys and multicolored birds that inhabit the area. After leaving the village, the footpath Meanders first beside open and fertile fields, then drops into a deep rift that is spanned by an ancient, fortified stone bridge built in the seventeenth century by Portuguese adventurers and still in use. After a thirty-minute walk, a stiff climb up a grassy hillside is rewarded by a magnificent view of the falls, breaking the smooth edge of the rolling river into a thundering cataract of foaming water.

A rewarding but longer trek is to walk along the east bank all the way to the back of the falls; crossing the river by papyrus boat known as 'Tankwa'.