Numatongo (Ubuvumo)

Michael Laumanns - 29/11/2015

(North province, Virunga mountains, Musanze district) Co-ordinates: S 01"24,906’; E 029°43,376°. Alt. ca. 2,055 m. Explored by the 2003 Swiss-German speleological project. Close to the tarred main road between Ruhengeri and Bukamba and before one reaches a high voltage line, a large collapse doline can be found. From here a 2.5 m high tube leads towards SW but flattens out soon. The passage has bat guano and some human bones. The main part of the cave develops from the doline towards the NE. The large tube has a height of over 4 m in the beginning. The NW gallery soon divides into a lava tube to the right, which soon ends in an earth plug, and a tube to the left that leads to a shallow doline that is used for agriculture. On the NE side of the doline the tube continues with two parallel running passages, the left of which hosts a considerable number of bats. Both passages re-join in a chamber that has another roof collapse. From here the tube gets gradually smaller and leads into an area that is characterised by much breakdown. The main tube continues a few metres to the E and is then plugged by earth. Throughout the cave one can find small lava stalactites as well as some calcite straws. Beside some bats white spiders, woodlice, flies and snail shells were seen. Survey and description according to Laumanns et al. (2004, 2007).