Known by the Maasai people as the “Mountain of God”, Oldonyo Lengai is nothing short of spectacular. Rising majestically from the Great Rift Valley floor to a height of 2890m, Oldonyo Lengai is the only active volcano on planet that erupts carbonatite lava. This type of lava is very unique because temperatures of these lavas are only around 5000C, about half the temperature of normal basalt lavas, and its lava flows with a viscosity almost as fluid as water.
Described by others as a scientifically precious, geochemical shrine, Oldonyo Lengai is quite a physically demanding climb. Its steep slope makes it a challenge to climb up as well as to climb back down and the day time heat is unbearable. The best time to climb the mountain is at night when the temperatures are lower. This allows the climber to witness the amazing sunrise at the summit and come back down before the scorching heat kicks in.
Mount Ol Doinyo Lengai also has phases of explosive activity during which the composition of the lava may contain much more silicate material. With this type of eruption, initial phases of the eruption may include strong lava fountains but usually there is no fluid lava and ash eruptions accompanied by ejection of rocks and explosions occurs. The two most recent eruptions of this type occurred during 1966-1967 and 2007-2008. Almost without fail, about every seven years Lengai erupts and plumes of smoke billow out of the crater. At other times it is possible to walk down into the crater, almost to the edge of the molten lava flows.
Views in the north from its summit crater lies the hot barren salt flats of Lake Natron stretch into the distance, beyond lies the Kenyan border. The day temperatures by the lake often exceed 40°C and a few animals survive here with the flamingo making its home here as breeding grounds, nesting on the salty surface on upraised mounds. The view on the east is dominated by Mt Kilimanjaro and to the west the forested escarpments and hills comprising the western slopes of the Great African Rift Valley.
To the south stretches the Crater Highlands, Ngorongoro being one of the prime wildlife conservation areas in Africa.
The ascent of Oldoinyo Lengai is demanding on account of the day time heat, lack of water, steep and unstable slopes of ash and crumbly rocks. An early start is recommended and the best approach is from the west where the morning sun can be avoided for a while
Given the long transfer distance, it is best to trek Oldonyo Lengai as part of a 3 day tour. Below is a standard 3 day itinerary for Oldonyo Lengai but keep in mind this climb can be an addition to a longer safari tour depending on your preference.
Depart Arusha early in the morning and drive to Lake Natron Camp (the transfer is around 6hours). Here you will be able to freshen up then visit Ngare Sero Waterfalls which descend from the Nguruman Escarpment west of Lake Natron. After your tour of the waterfalls you will head back to the camp for dinner and overnight.
After breakfast you will be transferred to Lake Natron, an alkaline lake that serves as the principal breeding site for three-quarters of the world’s population of Lesser Flamingoes. After your tour of Lake Natron you will head back to the camp so as to get enough rest before your trek up the mountain at midnight.
Your climb will start at midnight and it will take around 5 to 6 hours whereby you will reach the summit in time to witness the amazing sunrise as it illuminates the Great Rift Valley. During your climb you will be escorted by an experienced Maasai guide. After exploring the peak you will head back down the mountain to the base where your driver will be waiting for you to take you back to the camp to rest and freshen up. You will then be transferred back to Arusha via Ngare Sero Maasai village where you will be able to visit the Maasai bomas and experience their ways of life.