On the southeast along the Burundian border, Nyungwe National Park covers an area of approximately 970 km² of rainforest, bamboo, grassland, swamps and bogs. It hosts a large number of chimpanzees and a variety of other primate species including the L’Hoest’s monkey endemic to the Albertine Rift. The park is located in the watershed between the basin of the river Congo to the west and the basin of the river Nile to the east. From the east side of the Nyungwe forest comes also one of the branches of the Nile sources. The nearest town is Cyangugu, 54 km to the west. Mount Bigugu is located within the park borders. Nyungwe rainforest is probably the best preserved rainforest throughout Central Africa and one of the oldest rainforests in Africa. Primate tracking tops visitor’s list. There are 75 known mammals in Nyungwe, such as the cerval cat, mongoose, congo clawless otter and leopard to name but a few. 322 bird species have also been recorded. Memorable and photogenic moments include walking up to the Isumo waterfall or along the Canopy Walk suspension bridge. With plenty of rainfall, Nyungwe is also the major catchment area in Rwanda, and supplies water to 70% of the country. A ridge running through the forest forms a watershed between the drainage systems of the Nile and the Congo. A spring on the slopes of Mt Bigugu is said to be the most remote source of the Nile, the world’s longest river.