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Mountains cover 20 per cent of Africa’s surface area,
and over half of the 54 countries in Africa have
mountain peaks that rise 2,000 metres above sea
level. East Africa is one of the most mountainous
areas of Africa with several peaks above 4,500 metres,
and is home to the three highest mountains on the
continent: Kilimanjaro (5,895 m), Mount Kenya
(5,119 m) and the Rwenzori Mountains (5,109)
(Alweny and Gatarabirwa, 2014; UNEP, 2014).
Several mountains and mountain ranges in East
Africa stretch across borders. The Ethiopian
Highlands cross into Djibouti and Eritrea; the
Rwenzori Mountains, known as the ‘Mountains
of the Moon’ are shared between Uganda and the
Democratic Republic of Congo (DRC); while the
Virunga Mountains extend across Uganda, DRC
Overview of East Africa’s mountain areas
and Rwanda. Mount Elgon, Africa’s oldest volcano
is divided between Uganda and Kenya, while the
Eastern Arc Mountains extend 600 kilometres from
the south of Kenya to the southern part of Tanzania
(UNEP, 2014).
The majority of East Africa’s mountains are situated
along the East African Rift System, stretching 3,000
kilometres from Djibouti in the north to Malawi in
the south. The rift began to develop 22-25 million
years ago when the Somali plate broke away from the
African plate, also known as the Nubian. Today, it is
the largest active rift in the world. The rift is divided
into two parts: the Eastern Rift Valley (Ethiopia and
Tanzania) and the Western Rift Valley (Uganda and
Malawi). Two large mountain ranges, the Rwenzori
Mountains and Virunga Mountains, are situated
along the Albertine Rift at the northern end of the
Western Rift. The Ethiopian Highlands, Mount
Kilimanjaro, the Aberdare Mountains, Mount Kenya
and Mount Elgon are located along the Eastern Rift
(UNEP, 2014).
Volcanic mountains are the most common mountain
type along the East African Rift System, where the
majority of volcanic mountains in Africa are located
(UNEP, 2014). Formed during different time periods,
volcanic mountains are all made up of accumulated
lava and ash that erupted from below the earth’s
crust. Volcanoes are organized into three groups
depending on their activity status: active, dormant
and extinct. An active volcano has either historically
or recently erupted or shown signs of unrest (USGS,
2009). Examples of active volcanoes in East Africa
include Mount Nyiragongo and Mount Nyamuragira
– two of the eight volcanic mountains in the Virunga
Mountains (UNEP, 2014). Mount Nyamuragira
is Africa’s most active volcano with more than 40
eruptions since 1865 (SIGVP, 2015). Dormant
volcanoes have not been active for a long time, but
may show signs of unrest or may erupt again. Mount
Kilimanjaro and the other six volcanoes that make
up the Virunga Mountains are examples of dormant
volcanoes. Volcanoes that scientists consider unlikely
to erupt again are known as extinct volcanoes, such as
Mount Kenya and Mount Elgon (USGS, 2009; UNEP,
2014). Other important mountain types in East
Africa include massifs and highlands. Massifs form
when parts of the central block of the earth’s crust
cracks and opposing forces push the block upward.
Examples include the Rwenzori Mountains and the
Eastern Arc Mountains. Volcanic mountains can also
be massifs, such as Kilimanjaro, which is the largest
Agriculture and livestock, Kinigi, Rwanda