The mountain ranges of Kibimbi-Inanzegwe form a particular ecosystem of mountain rock ranges with many embedded valleys. These mountains are located straddling the municipalities of Bururi and Rutovu of the Bururi Provinces on one side and the municipalities of Makamba and Vugizo of the province of Makamba on the other side. Their ridges form boundaries between the natural regions of Bututsi and Buragane. Their altitude is between 1,500 and 2,500 m. The part of Buragane is characterized by abundant rains during the wet season (October and April). Temperatures vary from 17 to 23°C. The part of the Bututsi region is characterized by an altitude between 1800 and 2200 mm, an average annual rainfall of around 1300 mm and an average annual temperature of between 15 and 17°C.

On the hills the bushfires are very repetitive and the vegetation is very degraded. The vegetation consists of Eragrostis (Ishinge) and Hyparrhenia sp., Erica benguelensis, etc. with small shrubs mainly comprising Protea madiensis., Dissotis brazzae, small shrubs of Parinari curatellifolia, and Hyparrhenia sp., Koschya africana, with several species of ferns including Pteridium aquilinum var. aquilinum etc. and on the Makamilinum side etc. and on the Makamilinum side. In Inanzegwe, individuals of Osyris lanceolata are also observed.

The vegetation of forest galleries includes species of trees, shrubs, and grass species, woody species of exceptional biological diversity. Some of these species are characteristic of mountain forests. These include: Albizia gummifera, Anthocleista schweinfurthii, Macaranga capensis var. kilimandscharica, Myrianthus holstii, Bridelia micrantha,, Tabernaemontana stapfiana, Tabernaemontana stapfiana,, Cyathea manniana, Cyathea manniana, Cyathea manniana,, Cyathea manniana,, Cyathea manniana,, Cyathea manniana,, Brillantaisia cicatricosa,, Xymalos monospora, Melchioria schliebenii, Leptogenii, Derris harmsiana, etc. Outstanding species such as Prunus africana, Entandrophragma excelsum, Carapa procera. var. procera and Chrysophyllum gorungosanum have also been observed.