Cameroon's geography: a volcanic chain that sends its rivers four ways

How the volcanic chain crosses Cameroon

Britannica describes the country as triangular. The broad side lies along the south, from the Atlantic coast east to the Sangha River, and the apex is a narrow northern tail that reaches Lake Chad at 13°05'N. Between them the territory spans latitudes 1° to 13°N and longitudes 8° to 17°E. The record gives the area as 475,442 km²; the World Factbook figures reproduced on Wikipedia give a total of 475,440 km², of which 472,710 km² is land and 2,730 km² water.

The relief is concentrated on the western side of that triangle. Britannica attributes it to a volcanic rift that runs north from the island of Bioko, offshore in the Gulf of Guinea, and comes ashore as Mount Cameroon. From the mountain an irregular chain of high ground known as the Cameroon range follows the Nigerian border north-east almost to Lake Chad. It takes in the Bamenda, Bamiléké and Mambilla highlands and the Western High Plateau, and further north the Gotel Mountains, which trend south to north and end in the Mandara Mountains of the far north-west.

Mount Cameroon, whose summit is called Fako, rises to 4,095 metres so close to the shore that its mass reaches almost to the sea, where the coastal plain elsewhere runs 15 to 150 km inland. It is an active volcano, and the Canadian government's travel advice states that eruptions can occur at any time. The Factbook adds a wider note: thermal springs and indications of current or prior volcanic activity occur throughout the country. It also records the name sometimes given to Cameroon, "the hinge of Africa", and Britannica places it at the junction of western and central Africa.

The volcanic ground is also where the farming soils are best. Britannica's third soil group gathers young soils that include andosols, developed from volcanic ash, and Wikipedia's account of the relief puts some of Cameroon's most fertile soils around Mount Cameroon. The coast carries the same division in its sand. Limbe, in the South-West Region, has a black volcanic beach. Kribi, further south on the same coast, has white sand.

What happened at Lake Monoun and Lake Nyos

Volcanism in the western highlands created crater lakes, and two of them have killed people by releasing gas. On 15 August 1984 Lake Monoun released a large volume of carbon dioxide that suffocated 37 people. On 21 August 1986 Lake Nyos did the same, killing as many as 1,800 people and 3,500 livestock by the count in Wikipedia's history of Cameroon; the main country article gives between 1,700 and 2,000 deaths.

Both events are classed as limnic eruptions, and the same history article states that they are the only recorded instances of the type, while geological and sedimentary evidence suggests earlier ones may have caused large local die-offs before records began. The World Factbook entry for Cameroon lists them as its natural hazards, with the two dates and the two death tolls and nothing else under the heading.

The hazard has not been retired. Canada's travel advice for Cameroon, read in October 2026, says the Nyos and Monoun lakes sometimes release dangerous toxic gases, and tells travellers to consult local authorities and follow levels of volcanic activity in the local media before going to these areas. The same page carries the warning about Mount Cameroon. Between them the two notices cover the coastal and the inland ends of one volcanic chain.

Why the Adamawa Plateau divides north from south

From the forested southern plateau the land rises northward to the Adamawa, written Adamaoua in French, a grassy and rugged upland that stretches east from the western mountains across the country. Wikipedia describes it as a barrier between the north and the south. Its height is given three ways: an average of 1,100 metres in the main country article, 1,000 metres in the geography article, and between 750 and 1,350 metres in Britannica. Average temperatures on the plateau run from 22 to 25 °C, with heavy rain between April and October peaking in July and August.

The plateau is the line along which most of the country's other divisions fall. South of it the South Cameroon Plateau sits at an average of about 650 metres under equatorial rainforest, less humid than the coast because it alternates wet and dry seasons. North of it the land falls away through the Bénoué depression to the northern lowland, at 300 to 350 metres, a savanna plain that declines toward the Lake Chad basin. Britannica notes the inselbergs scattered across it, mounds of erosion-resistant rock left standing above the plain.

People are distributed along the same line. Wikipedia's account of the population states that the Adamawa broadly bisects the country's 230 to 282 ethnic and linguistic groups into northern and southern divisions. Sudanic groups live in the central highlands and the northern lowlands, and the Fulani are spread through the whole north. Bantu speakers hold the coastal and equatorial zones, and Semi-Bantu speakers the western grassfields. The plateau itself, together with the south-eastern Bénoué depression and most of the South Cameroon Plateau, is listed among the sparsely populated parts of the country.

Where the rivers of Cameroon drain

Both Wikipedia and Britannica count four drainage systems, and each leaves the country in a different direction.

Which rivers run straight to the sea

South of the Adamawa the principal rivers, the Sanaga, the Wouri, the Nyong and the Ntem, flow south-west or west directly into the Gulf of Guinea. North of the coast the Akwayafe and the Manyu run west, the Manyu joining the Cross River in Nigeria. Rapids and waterfalls obstruct the southern rivers, and those same sites supply most of the country's energy: the Sanaga drives the principal hydroelectric station, at Edéa, and the rest of the supply comes from oil-powered thermal engines. The African Development Bank's economic outlook credits part of the growth recorded in 2025 to energy production from the new Nachtigal dam, which added 420 megawatts.

The Wouri gave the country its name. Portuguese sailors reached the coast in 1472 and called the estuary Rio dos Camarões, the river of prawns, after the ghost shrimp they found in it. Britannica records that Camarões was also used for the neighbouring mountains, that English usage confined "the Cameroons" to those mountains until the late 19th century, and that in 1884 the Germans extended Kamerun to their whole protectorate. Douala, the economic capital and the main seaport, stands on that estuary, and the coastal plain around it and around the Cross River estuary on the Nigerian border is fringed with mangrove.

Where the inland rivers go

The Dja and the Kadéï drain south-east instead, and the Dja joins the Sangha and reaches the Congo. The Sangha also fixes two of the country's extreme points: the easternmost lies in the river opposite the Congolese town of Bomassa, and the southernmost is a headland at its confluence with the Ngoko, immediately north of Ouesso in the Republic of the Congo.

North of the plateau none of the water reaches the Atlantic directly. The Bénoué runs north and west into Nigeria and empties into the Niger, and it is seasonally navigable from Garoua across the border. The Logone and the Chari form part of the eastern border with Chad and flow north into Lake Chad, which Cameroon shares with three neighbouring countries. The northernmost point of the country is an unnamed peninsula jutting into that lake.

The Factbook puts total renewable water resources at 285.5 km³ as of 2011, against withdrawals of 0.97 km³ a year in 2005, of which 68% went to agriculture.

How rainfall falls away from the coast

The country lies wholly within the tropics, and Britannica puts mean annual temperatures within the 20s °C everywhere except at altitude. What changes from south to north is the rain. Two air masses decide it: a dry continental air mass from the Sahara, which brings hot and dusty weather, and a humid maritime air mass from the Atlantic, which brings the rain-bearing winds. Precipitation decreases from the coast to Lake Chad.

What each zone receives

Along the coast the rainy season runs from April to November and the relatively dry season from December to March, with a transition in March and April marked by violent winds. Mean annual precipitation there exceeds 2,500 mm, falling on about 150 days. On the central plateau it drops to about 1,500 mm, spread across four seasons: a light rainy season in May and June, a short dry season from July, a heavy rainy season in October and November, and a long dry season from December. The north has a single dry season from October to May and an average of about 750 mm a year.

The volcanic chain breaks the gradient. Britannica places the wettest part of the country in the western highlands and gives Debundscha Point on Mount Cameroon a mean annual precipitation above 10,000 mm, most of it between May and October; the geography article on Wikipedia puts the Debundscha figure at 10,300 mm. Ten metres of rain a year on the coastal foot of the mountain and three quarters of a metre on the plain south of Lake Chad sit inside one country.

How the averages have moved

The World Bank's Climate Change Knowledge Portal gives the national averages for 1995 to 2014 as 24.48 °C and 1,739.93 mm of rain a year. Since 1970 temperature has risen at 0.29 °C per decade in the ERA5 reanalysis, and precipitation has changed by minus 62.06 mm per decade. For 2040 to 2059 under the high-emission scenario SSP3-7.0, the median projection is a further 1.43 °C, within a range of 0.83 to 1.96 °C, with a median precipitation change of 98.22 mm.

The north is where the change has been recorded on the ground. The Bertelsmann Transformation Index report for 2026 states that the northern regions have experienced desertification and more prolonged droughts, and that flooding between July and October 2024 in Logone-et-Chari and Mayo-Danay affected 200,000 people. The Factbook's list of environmental issues names overgrazing and desertification alongside deforestation, poaching and overfishing.

What grows between the mangroves and the acacias

Vegetation follows the rain northward in bands. Britannica describes the hot and humid south as dense rainforest in which hardwood evergreens, mahogany, ebony, obeche, dibetu and sapelli among them, may grow more than 60 metres tall, with large numbers of orchids and ferns beneath. Mangroves grow along the coast and at the mouths of rivers, and Wikipedia gives their extent as 270,000 hectares. Inland the rainforest gives way to the semi-deciduous forest of the central region, where a number of species shed their leaves in the dry season, and north of that to wooded savanna with scattered trees 3 to 18 metres high. Toward the Chad basin the trees thin out and are mainly acacias.

The mountains add a second, vertical sequence. Between about 1,200 and 2,400 metres the rainforest changes character: the trees are smaller, of different species, and hung with mosses, lichens and other epiphytes. Above it come drier woodland, tall grassland or patches of mountain bamboo. Short grasses take over above about 2,400 metres in the interior and above about 3,000 metres on Mount Cameroon.

How much forest the country holds

Forest covered about 43% of the land in 2020, or 20,340,480 hectares, down from 22,500,000 hectares in 1990. Almost all of it was naturally regenerating; planted forest accounted for 61,100 hectares in 2020. Around 15% of the forest area lay within protected areas in 2015, and all of it was reported to be under public ownership.

Global Forest Watch, using Landsat imagery, reports cumulative tree cover loss of 2,226,205 hectares from 2001 to 2024, about 7.1% of the tree cover the country had in 2000. The 2026 Bertelsmann report puts the rate of deforestation over the past decade at approximately 1% a year and attributes it to investment in palm oil, mineral extraction and road building. Britannica's account of the economy observes that forestry has been largely limited to the accessible areas along the Douala to Yaoundé railway and the main roads, with expansion into new areas under way.

The government's own reading of its forests appears in its 2026 submission under the UN REDD+ framework. It proposed a national forest reference level of zero, using a reference period of 2000 to 2020, on the argument that Cameroon is a net carbon sink at national level and that results-based payments should be claimed only for net removals.

The species counts differ by source. The main Wikipedia article records 8,260 plant species with 156 endemic, 409 mammals with 14 endemic, 690 birds with 8 endemic, 250 reptiles and 200 amphibians; the geography article gives 9,000 plants, 900 birds and 320 mammals, with the same endemic counts. Neither gives the year of the count. Britannica lists chimpanzees, mandrills, red and green monkeys in the forest, and a few surviving elephants in the forest and the grassy woodland, where baboons and several types of antelope are the commonest animals.

Which ground the reserves were drawn around

Protected areas began in the north. The colonial administration created the first two reserves in 1932, Mozogo Gokoro and Bénoué, and the Waza reserve followed on 24 March 1934. Britannica records that Waza was originally set up to protect elephants, giraffes and antelope, and that it holds lions, leopards and birds from pelicans to spotted waders. Wikipedia gives reserve coverage as about 4% of the country at the start, rising to 12%, with a stated aim of 30%.

The World Database on Protected Areas, as Protected Planet displayed it in October 2026, listed 54 protected areas covering 10.99% of the land, 51,089 km² of a land area it measures at 464,782 km². Half of them, 27, are in category II. Marine and coastal protected areas covered 1,737 km² of 15,192 km², or 11.43%. The national data behind those figures was last updated in 2021 by the Ministry of Forestry and Wildlife, through the Central African Forests Commission.

Cameroon ratified the World Heritage Convention on 7 December 1982, and three of its properties are inscribed, two in the southern forest and one in the far north.

The Dja reserve is bounded by its own river, which forms its natural limit on almost every side. UNESCO counts 107 mammal species there, five of them threatened, and at least 14 primates, including the western lowland gorilla, the chimpanzee and the mandrill. Agriculture and commercial hunting are prohibited, and the Baka who live in the reserve are permitted to hunt in the traditional way. In the Sangha Trinational, Lobéké is the one park of the three with use zones inside it; in the Central African Republic and the Congo, local resource use is not permitted in the protected areas.

How the coast and the borders were settled

The coastline runs for 402 km on the Bight of Biafra, and Cameroon claims a territorial sea of 12 nautical miles. The westernmost point of the country is an unnamed spot on Akwabana Island.

The land boundaries total 5,018 km in the Factbook figures, shared with six neighbours.

The Nigerian border is the one that follows the volcanic chain, and it is the one that was fought over. Some sections of the country's borders follow rivers, among them the Aïna, the Akwayafe and the Ntem, also called the Campo. The Bakassi peninsula, between the Cross River estuary and the Rio del Rey estuary, was administered by Nigeria through the colonial era, but a 1913 agreement between Britain and Germany had placed it in German Kamerun. Nigeria pointed to other colonial documents and to its long administration. Oil discoveries sharpened the dispute, forces from the two countries clashed in 1981, and on 29 March 1994 Cameroon referred the matter to the International Court of Justice.

The court ruled in Cameroon's favour in October 2002. Nigeria resisted the ruling, and the Greentree Agreement of 2006 set out a transfer of administration over two years: part of the peninsula was handed over in August 2006 and the remainder in 2008. Many inhabitants kept their Nigerian citizenship. The eastern frontier has its own unfinished work: in 2022 Cameroon and the Central African Republic agreed to demarcate the border between them.

Where people live on this ground

The record puts the population at 28,372,687 in 2023. Wikipedia describes it as almost evenly divided between town and country, and Britannica gives the urban share as 59.9% in 2024. Density is highest in the large urban centres, the western highlands and the north-eastern plain. The Adamawa, the south-eastern Bénoué depression and most of the South Cameroon Plateau are thinly settled, so the volcanic highlands carry many more people than the plateau that dominates the map.

The two capitals sit on different ground. Douala, on the Wouri estuary, holds more than 75% of the country's industrial capacity together with neighbouring Bonabéri, and it is the principal seaport; a deepwater port at Kribi, further south, began operations in 2014. Yaoundé, the political capital, lies in the south-central part of the country, and the record gives its population as 2,440,462 in 2012.

Farming follows the same zones the rain draws. The coastal soils and climate favour commercial plantations of bananas, cocoa, oil palms, rubber and tea. On the South Cameroon Plateau the cash crops include coffee, sugar and tobacco, coffee is the main cash crop of the western highlands, and in the north conditions favour cotton, groundnuts and rice. Arable land made up 13.12% of the country and permanent crops 3.28% in 2012, and the remaining 83.61% fell under other uses.