Ol Doinyo Lengai — Mountain of God

Ol Doinyo Lengai — 'Mountain of God' in the Maasai language — is one of the most scientifically extraordinary volcanoes on Earth and one of East Africa's most demanding climbs. Rising to 2,962 metres from the floor of the East African Rift Valley on the southern shore of Lake Natron, Lengai is the world's only active volcano that erupts natrocarbonatite lava — a unique lava type that is cooler than conventional basaltic lava (only 500°C vs 1,200°C), emerges jet-black, and turns brilliant white within hours of exposure to rain and humidity as the unusual mineral composition carbonates. The volcano is deeply sacred to the Maasai people, who hold it as the dwelling place of Engai, their supreme deity, and continue to conduct ceremonial pilgrimages to the crater. The summit climb — typically attempted overnight to avoid the extreme heat of the lower slopes during daylight — involves steep ash and loose scree, gaining 1,500+ metres from the base camp on the lake shore. Summit temperatures can drop to -5°C on clear nights. The view from the crater rim at dawn — Lake Natron's red alkaline flats, the Serengeti plains, and Ngorongoro's caldera — is regarded as one of Africa's most extraordinary natural panoramas. Source: Keller, J. et al. (2010), 'Geochemistry of Ol Doinyo Lengai carbonatites', Journal of Petrology.