I.

Introduction

Congo, river, primarily in the Democratic Republic of the Congo (formerly Zaïre), the second longest river in Africa, and one of the longest in the world. The Congo, about 4,375 km (2,720 mi) long, ranges in width from 0.8 to 16 km (0.5 to 10 mi). The total length of navigable routes on the Congo and its tributaries is about 14,484 km (9,000 mi). The river and its tributaries provide the main artery of transport in central Africa and drain the region’s vast equatorial basin. To date little exploration of the Congo Basin has taken place. However, its hydroelectric potential is estimated to be as much as one-eighth of the world’s total.

The upper Congo River is characterized by a number of lakes, waterfalls, and rapids. The middle section dips down a series of seven cataracts known as Boyoma Falls. The lower Congo River divides into two branches, forming the Pool Malebo. Fed steadily by rain throughout the year, the flow of the river is quite regular. The Congo River holds numerous sandbars and thousands of islands, many of which are cloaked in evergreen trees. The basin is densely blanketed with tropical vegetation, bordered by belts of savannah. The rich wildlife of the river includes crocodiles and numerous species of fish.

II.

Course of the Congo

Formed by the junction of the Lualaba and Luvua rivers in the south of the Democratic Republic of the Congo, it flows generally north as far as Stanley Falls, just south of the equator. From this point the course resembles a huge irregular arc, looping north-east, west, and south to an outlet on the South Atlantic Ocean, where the volume of discharge approximates 34 million litres (7.5 million gallons) per second at high water. More than 4,000 islands, including approximately 50 more than 16 km (10 mi) long, are situated in the river. South of its junction with the Ubangi River, the chief northern tributary, to a point below Pool Malebol (Stanley Pool), the River Congo is part of the boundary between the Republic of the Congo and the Democratic Republic of the Congo.

With its numerous tributaries, which also include the Aruwimi, Kasai, and Lomami rivers, the Congo drains the central African equatorial basin, an area of more than 4.1 million sq km (more than 1.6 million sq mi) and provides the main artery of transport in central Africa. This drainage basin includes most of the two republics previously named, northern Angola, western Zambia and Tanzania, and southern Central African Republic. The region is densely covered, particularly in the river valleys, with tropical vegetation.

In the descent from the western region, the lower Congo courses through a series of cataracts, known collectively as Livingstone Falls, the southernmost of which is a short distance north of Matadi, the leading port of the river estuary. This section of the river, about 400 km (250 mi) long, is unnavigable. Below Matadi, where the Congo estuary begins, the river is navigable to the sea, a distance of about 134 km (83 mi). The only impediment to navigation on the upper Congo is the series of cataracts at Stanley Falls near Kisangani. Between this point and Kinshasa (formerly Léopoldville), the capital of the Democratic Republic of the Congo, which is at the northern terminus of the cataracts, the river is navigable to all types of river craft. Many of them are operated on regular schedules on this route, which is about 1,600 km (1,000 mi) long, as well as on most of the Congo tributaries.

III.

European Exploration

The first European, so far as is known, to visit the river was the Portuguese navigator Diogo Cam (Port. Cão), who entered the Congo estuary on a voyage between 1482 and 1484. He claimed the surrounding region as Portuguese territory, leaving a marble pillar on the riverbank as proof of his discovery. From this circumstance the river became known as the Rio de Padrão (Pillar River). This name was subsequently replaced by Zaïre, a term similar to the local word for river, which gave way in turn to the present name.

After Cam's voyage other Europeans visited the river estuary, chiefly for trading purposes, but more than three centuries elapsed before a serious exploratory project was undertaken. In 1816 a British expedition reached a point between present-day Matadi and Kinshasa, failing to advance farther because of an outbreak of illness among the members. The Scottish explorer and missionary David Livingstone reached the Lualaba River in 1871; the first exploration of the main stream was the expedition of the Anglo-American explorer Henry M. Stanley. Stanley descended the Lualaba-Congo river system in 1876 and 1877 to its mouth, travelling more than 2,575 km (1,600 mi). As a navigable route to the interior, the Congo figured prominently in the subsequent colonization of central Africa.