The Niger
The Niger is the main river of West Africa and the third longest river on the continent. It is famous for its unusual boomerang-shaped course: it flows north into the desert, then swings around and flows back south, eventually reaching the Atlantic Ocean. The river passes through five countries and ends in a vast oil-rich delta in Nigeria.
- Length4,180 kmThird longest river in Africa
- Countries5Guinea, Mali, Niger, Benin, Nigeria
- SourceGuinea HighlandsJust 240 km from the Atlantic, but the river goes the long way
- MouthGulf of GuineaThrough a huge delta in Nigeria
- ShapeA boomerangFlows north, then east, then south
- Famous cityTimbuktuOn the river's northernmost stretch in Mali
The Niger compared to Africa's great rivers
The Niger is the third longest river in Africa after the Nile and the Congo. It takes a much longer route to the sea than its straight-line distance would suggest.
What is the Niger?
The Niger starts in the highlands of Guinea, just 240 km from the Atlantic coast. But instead of flowing west to the sea (the obvious route), it flows northeast into the dry Sahel region of Mali. It reaches the edge of the Sahara desert at the city of Timbuktu, makes a great curve, and then flows southeast across Niger and Nigeria to the Gulf of Guinea. Geographers think the river's unusual shape was caused by climate change: there were once two separate rivers that joined up when the climate became drier.
The Inner Niger Delta
In Mali, the Niger spreads out into a vast wetland called the Inner Niger Delta, even though it is hundreds of kilometres from the sea. Every wet season, the river floods over an area roughly the size of Belgium, creating a temporary wetland in the middle of the Sahel. The flooded delta is one of the most important wetlands in Africa, supporting around a million people who fish, herd cattle and grow rice in the floodwaters.
Timbuktu and the medieval empire
The city of Timbuktu, on the northernmost stretch of the Niger in Mali, was once one of the wealthiest cities in the world. In the 14th and 15th centuries it was the capital of the Mali Empire, controlling the trans-Saharan trade in gold, salt and slaves. The most famous Mali emperor, Mansa Musa, was probably the richest man who ever lived: when he made the pilgrimage to Mecca in 1324, he gave away so much gold along the way that he reportedly crashed the value of gold in Egypt for over ten years.
Timbuktu was also a centre of learning. Its universities and libraries housed hundreds of thousands of manuscripts. Many of these treasures were lost when the Songhai Empire fell in the 1600s, but tens of thousands of medieval manuscripts have survived and are still being preserved today.
The Niger Delta and oil
The Niger ends in a vast triangular delta in southern Nigeria. The Niger Delta contains some of the largest oil and gas reserves in Africa. Since oil was discovered in 1956, hundreds of billions of dollars worth has been pumped from beneath the delta. Almost none of that wealth has reached the local people, who live in some of the most polluted conditions in the world.
Oil spills, gas flaring and pipeline leaks have devastated the delta's ecosystems. Fish stocks have collapsed, farmland has been poisoned, and life expectancy in some delta areas is around 40 years. The delta has been the site of long-running protests, armed insurgencies and government violence over the unequal distribution of oil wealth.
Deeper dive: the two-rivers theory, the Sahel and the Lagos megacity
The Niger's strange boomerang shape was one of the great geographical puzzles for European explorers in the 18th and 19th centuries. The Scottish explorer Mungo Park, after two expeditions, was the first European to confirm in 1796 that the upper Niger flowed eastward (towards the desert) rather than westward (towards the Atlantic). It took another 30 years and many more deaths from disease before the brothers Richard and John Lander finally traced the river to its mouth in the Gulf of Guinea in 1830, proving the connection between the upper Niger of Mali and the Niger Delta of Nigeria.
The boomerang shape is now thought to be the result of river capture. Until approx. 5,000 years ago, the climate of West Africa was much wetter, and the upper Niger emptied into a large lake in what is now the Sahara. As the climate dried, this lake shrank and disappeared. The southern Niger (which was originally a separate river) gradually eroded its way northward and eventually "captured" the waters of the upper Niger near present-day Timbuktu. The Inner Niger Delta is a remnant of the ancient lake bed.
The Niger Delta is now one of the most densely populated areas in Africa, home to over 30 million people including many distinct ethnic groups. Just west of the delta on the coast is Lagos, the largest city in Africa and one of the fastest-growing megacities in the world. Lagos's population was around 200,000 in 1950; today estimates range from 15 to 25 million. The city is largely built on islands and lagoons in the western edge of the Niger Delta region, although it is not formally part of the delta. Lagos faces serious challenges of flooding, traffic, infrastructure and rising sea levels, but it is also one of the most economically dynamic cities in Africa.
The country at the river's mouth is Nigeria. The longest river in Africa is the Nile.