Visible from space, Africa's Great Rift Valley runs three thousand miles from the Red Sea to the mouth of the Zambezi. It's a diverse terrain of erupting volcanoes, forest-clad mountains, spectacular valleys, rolling grasslands, huge lakes and mighty rivers, and is home to crocodiles, hippos, lions, elephants, flocks of flamingos and a diversity of indigenous peoples. / Using state-of-the-art high definition filming techniques, this series investigates the geological forces which shaped East Africa's Great Rift, and which make it one of the world's most wildlife-rich landscapes. / The valley is the product of deep-seated geological forces which have spewed out a line of cloud-wreathed volcanoes stretching from Ethiopia to Tanzania. Their peaks provide a refuge for East Africa's most extraordinary wildlife, including newly discovered and previously unfilmed species which have evolved surprising survival.