The "Mountain of God" to the Maasai — an active volcano near Lake Natron, and the only one on Earth erupting natrocarbonatite lava. Climbed overnight, it is one of Tanzania's toughest short treks.
Ol Doinyo Lengai stands 2,962 m above the Rift Valley floor south of Lake Natron, a near-perfect ash cone that is still active — its unique, relatively cool black lava turns white as it weathers, streaking the summit crater. It is sacred to the Maasai, who live in the plains around it.
The climb is short but brutal: groups leave around midnight and climb roughly 1,600 m of loose ash and steep rock in five to seven hours to reach the crater rim at dawn, then descend in the heat of the morning before the surface becomes an oven. There is no shade, no water and a lot of scrambling near the top. It suits fit, determined trekkers looking for something wilder than Kilimanjaro, and pairs naturally with Lake Natron's flamingos and the nearby Engare Sero footprints.