Lake Bogoria has Africa's only real geyser field along one shore and, when the birds are in, up to a million flamingos feeding along the other. It lies in a narrow trench on the floor of Kenya's Rift Valley, under the dark six-hundred-metre wall of the Siracho Escarpment, and the geysers are the rarer half. Fewer than a thousand exist anywhere on Earth, most of them clustered in Yellowstone, Iceland, Kamchatka and New Zealand; here molten rock sits unusually close to the surface under a young rift. At Loburu, on the western side, some two hundred springs steam along the shore, and jets of scalding water go up in sudden roaring plumes. You stand close enough to feel the heat on your face and watch the steam bend off on the wind. One vent, catalogued as KL30, has run on a steady forty-five-minute cycle and is reckoned the tallest natural geyser on the continent. A high lake can drown the vents and silence them for years.
The springs are hot enough to cook in. A guide lowers eggs or maize into one for you and lifts them out done a few minutes later, steam hissing round your boots and the sulphur thick over everything. Behind the shore, scrub and acacia hold one of Kenya's best populations of greater kudu, the males with long spiralled horns. The flamingos work the shallows in a restless pink ribbon, sieving algae with their bills upside down and lifting all together when something startles them. Their colour is borrowed from the pigment in what they eat, and the same rich broth killed tens of thousands of them in the 1990s for reasons still argued over. None of this is anyone's to give. The Endorois were herding these shores long before the reserve and were evicted in the 1970s; in 2010 an African commission ruled the land theirs and ordered it returned, and little has happened since. The birds keep coming because the heat under the western shore never stops boiling the lake down, so it stays thick when its neighbours flood.