MT. OLDONYO LENGAI
Ol Donyo Lengai is a volcano located in the north of Tanzania and is part of the volcanic system of the Great Rift Valley in Eastern Africa. It is located in the eastern Rift Valley, south of both Lake Natron and Kenya.

It is unique among active volcanoes in that it produces natrocarbonatite lava, a unique occurrence of volcanic carbonatite. Further, the temperature of its lava as it emerges is only around 510 °C (950 °F). A few older extinct carbonatite volcanoes are located nearby.

Ol Donyo Lengai means "Mountain of God" in the Maasai language of the native Maasai people the record of eruptions on the mountain dates to 1883, and flows were also recorded between 1904 and 1910 and again between 1913 and 1915. A major eruption took place in June 1917, which resulted in volcanic ash being deposited about 48 kilometres away.

A similar eruption took place for several months in 1926 and between July and December 1940, resulting in the ash being deposited as far as Loliondo, which is 100 kilometres away. Several minor eruptions of lava were observed in 1954, 1955, 1958 the early 1960s.