Lualaba River

The Lualaba River flows entirely within the eastern Democratic Republic of Congo. It is the greatest river source (headstream) of the Congo River by volume of water. The Lualaba is 1,800 kilometres (1,100 mi) long. Its headwaters are in the country's far southeastern corner near Musofi and Lubumbashi in Katanga Province, next to Zambia. The Chambeshi River is the longest river source (headstream) of the Congo.

The origination of the Lualaba River is on the Katanga Plateau, at an elevation of 1,400 metres (4,600 ft) above sea level. Its total course flows northward to end near Kisangani, where the name Congo River officially begins.

From the Katanga Plateau it drops, with waterfalls and rapids marking the descent, to the Manika Plateau. As it descends through the upper Kamalondo Trough (Upemba Depression), 457 metres (1,499 ft) in 72 kilometres (45 mi), near Nzilo Falls it is dammed for hydroelectric power at Nzilo Dam.

At Bukama in Haut-Lomami District the river becomes navigable for about 640 kilometres (400 mi) through a series of marshy lakes in the lower Upemba Depression, including Lake Upemba and Lake Kisale.

Ankoro lies on the west bank of the Lualaba River, opposite its confluence with the Luvua River from the east. Some geographers call the combined river below this point the "Upper Congo".

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