With only 480km of paved roads, flying is the best (and often the only) way of getting around the DRC, although the poor safety record of Congolese air traffic has led all but one (Bravo Air Congo) of its airlines to be banned from operating in Europe. Domestic airlines include Hewa Bora Airways, Congo Airlines and Lignes Aeriennes Congolaises, all with offices at the airport or you can book through travel agents.
Train travel is possible from Kinshasa to Matadi, Lumbumbashi to Ilebo and Kalemie via Kabalo. There is an isolated branch of the Great Lakes railway line that runs between Kisangani and Ubundu in order to bypass the Boyoma (Stanley) Falls on the Congo River, but trains here are sporadic and there are no connections through to Kindu.
If you have enough time and aren’t fussy about privacy there are possibilities to travel by barge along the Congo River from Kinshasa to Kisangani. This is the real highway of Central Africa and a wonderful way to see the country. However, there is no fixed timetable for the departure of barges and they often break down or get stuck on sandbanks along the way.