Kenya Lake System in the Great Rift Valley, Natural lake system in Great Rift Valley, Kenya.

The Kenya Lake System in the Great Rift Valley comprises Lake Bogoria (10,700 ha), Lake Nakuru (18,800 ha) and Lake Elmenteita (2,534 ha), three shallow alkaline lakes on the rift floor. Their waters are rich in blue-green algae that feed insect larvae, small crustaceans and lesser flamingos, and the lakeside silts are trampled and probed by the birds. The photograph shows a broad band of pale pink and white flamingos standing in shallow water, with dark hills and a hazy blue sky behind.

The three lakes belong to the Kenya lake system, part of the Gregory Rift, the eastern branch of the East African Rift that runs from Tanzania into Ethiopia. The rift's floor is broken by volcanoes, some still active, and the lakes lie among them. The Tugen Hills west of Lake Baringo hold fossils preserved in lava flows from 14 to 4 million years ago, including hominid remains.

The lakes' algae-rich water feeds insect larvae and small crustaceans, which in turn feed lesser and greater flamingos. The birds' trampling compacts lakeside silts, and their probing beaks oxygenate the mud; preserved nest mounds leave irregularities in the shoreline. Lake Bogoria, Nakuru and Elmenteita form the Kenya lake system, a key feeding area for lesser flamingos.

Each lake has viewing points along access roads where you can watch birds and other animals. The paths vary from flat ground to steep slopes, so wear sturdy shoes and bring water.

The lake system holds the world's most important feeding area for lesser flamingos, and thirteen globally threatened bird species occur here. The birds' trampling and probing beaks alter the lakeside silts, and their cemented nest mounds leave irregularities in the shoreline topography as water levels change.