Series investigating the geological forces which shaped East Africa's Great Rift Valley and which make it one of the world's most wildlife-rich landscapes

Visible from space, Africa's Great Rift Valley runs three thousand miles from the Red Sea to the mouth of the Zambezi.

The Great Rift Valley channels a huge diversity of waterways - rivers, lakes, waterfalls, caustic springs and coral seas - spanning from Egypt to Mozambique. Some lake and ocean deeps harbour previously unseen life-forms, while caustic waters challenge life to the extreme.

The Great Rift Valley provides the stage for an epic battle between trees and grass - its course influenced by volcanic eruptions, landscape and rainfall. On its outcome rests the fate of Africa's great game herds.