It may roughly be divided into four zones: - (1) the small coast zone west of the Crystal Mountains, through which the Congo breaks in a succession of rapids to the Atlantic; (2) the great central zone, described below; (3) the smaller zone east of the Mitumba range (including the upper coursesof some of the Congo tributaries which have forced their way through the mountains), and west of Lake Mweru and the upper course of the Luapula; and (4) an area which belongs geographically to the Nile valley.
Mitumba range extends from the south-eastern frontier of the colony, in a north-easterly direction towards Lake Tanganyika, and northwards along the western shore of that lake past lakes Kivu and Albert Edward to Albert Nyanza, forming the western edge of the western or Albertine rift-valley.
The central zone dips with a westerly inclination from the Mitumba Mountains towards the western edge of the plateau.
The wooded savannas are mostly situated on the higher lands of the central zone, where the land dips down from the Mitumba Mountains to the Congo.
It lies west of the Lualaba on the Mitumba range, in about 11 ° S., 25° 45' E.