Straddling the equator, the country now called the Democratic Republic of the Congo (DRC) is home to 50 million people. Its area of 905,354 square miles, the third largest in Africa, easily compares to that of Western Europe or the US east of the Mississippi. It has been populated for about 10,000 years, at first solely by pygmee hunter-gatherers; Bantu-speakers arrived early in the first millenium A.D and practised a wide range of life-styles including agriculture. When 'discovered' by Europeans in the late 15th century the area may have held a population of as much as 25 million divided on about 250 ethnic groups. The latter number still holds up.
Like its smaller neighbor the Republic of the Congo, the DRC is named for the Congo River; the world's fifth longest and second only to the Amazon in watershed and volume. This river drains the vast Central African equitorial basin, a low-lying plateau whose northern zone is mostly covered by sixty million year old tropical rain forest, making up more than a quarter of all the forest in the world. So dense is it in parts that sunlight cannot reach the forest floor, which is what gave rise to the idiom of 'darkest Africa.'
Flowing through this landscape, one of the lushest ecosystems on earth, the Congo River and its numerous tributaries represent nearly 9,000 miles of navigable waterways. These remain the foremost means of communication in a war-torn land where decent roads are few.
Yet much of the Lower Congo is rendered unpassable to all but small river craft by a series of fierce rapids and cataracts, the Livingstone Falls. Beginning 100 miles from the river's Atlantic mouth and extending 220 miles inland past the Crystal Mountains, it corresponds to the power of all rivers and falls in the US combined, which hindered European exploration until the mid-19th century. However, upstream from where the world's two most proximate capitals, Brazzaville (the Republic of the Congo) and Kinshasa (DRC) face each other across a lakelike expanse known as Malebo Pool, the 1,000 square miles stretch called the Middle Congo is navigable and up to ten miles wide.
Still farther upstream, and bending southwards toward its headwaters, the Upper Congo is also known as the Lualaba. David Livingstone hoped this might be the elusive source of the Nile, a notion refuted by the first European to descend the length of the Congo, Henry M. Stanley. The Lualaba begins at the Boyama (or Stanley) Falls above the city of Kinsangani, the location of the 'Inner Station' in Joseph Conrad's Heart of Darkness. Passing west of the Ruwenzori Range, a chain of alpine volcanic peaks which Ptolemy called 'the Mountains of the Moon,' the Upper Congo leads into a savannah-covered highland of enormous mineral riches.
These include the world's largest deposits of uranium; the material for the atomic bombs used in WWII derived from this Shaba province. Formerly called Katanga, its 1960 secession from the newly independent Congo provoked one of the major international crises in the postwar era and the first coup d'état in a former African colony.