The 1.25 mile long cave is home to a large bat colony. Most of the caves in Rwanda are developed from Cenozoic volcanic rocks for instance Manjari which is 1.660 m and Nyiragihima in Ruhengeri which 1.116 m (Northern Province). There are in total 52 surveyed caves in the province with 15.2 km cave passages.
The longest cave of Rwanda is called “Ubuvumo Bwibihonga” a multi-level system of parallel lava tubes with 4.530 m length.
The commonly visited cave is called Musanze cave which is 2 km long; it lies in the volcanic region where lava flow layers dating from 65 million years ago to today have created the Albertine Rift Valley. The cave has 31 entrances, most being roof collapses.
It is formed from lava basaltic layers from the Bisoke and Sabyinyo volcanoes. The cave entrance is vast, exceeding 10 km and it is well proportionate with several side passages leading off from the main cave. Bat roots are a feature of the cave and the collapses create a truly incredible array of coloured shafts of light.
(A cave or cavern is a natural underground space large enough for a human to enter. Some people suggest that the term cave should only apply to cavities that have some part that does not receive daylight; however, in popular usage, the term includes smaller spaces like sea caves, rock shelters, and grottos.
Speleology is the science of exploration and study of all aspects of caves and the environment which surrounds the caves. Exploring a cave for recreation or science may be called caving, potholing, or, in Canada and the United States, spelunking.)