Mahale Mountains National Park

Established in 1985 and covering 1,613 square kilometres, Mahale has no roads: you arrive by light aircraft and then boat along the shore of Lake Tanganyika, the world's second-deepest and second-oldest lake, roughly 90 per cent of whose fish species are found nowhere else.

The forested slopes are home to around 800 chimpanzees, one group of which has been studied since the 1960s and is habituated to people. Trekking to find them can take anything from twenty minutes to several hours of steep forest walking, and time with the group is limited to one hour to protect them. Beyond the chimps there are red colobus and other primates, forest birds, and the lake itself — clear enough to snorkel among the endemic cichlids, and a place to kayak and swim between treks. Mahale is usually paired with Katavi.