What it is
About 3,300 square kilometres of lowland rainforest in the southwest, near the Liberian border. UNESCO listed it in 1982. The chimpanzees here have been studied continuously since the 1970s and are documented using stone and wooden hammers to crack nuts.
Why go
The forest itself is the rarest thing in it: most of the Upper Guinean forest belt has been cleared, and this is the largest block left. Pygmy hippopotamus, forest elephant, several duiker species and eleven primate species are present, though the forest is dense and sightings of anything large are uncommon. Some habituated chimpanzee groups can be tracked on foot with researchers or park guides.
When to go
The dry months, December to March. Be honest with travellers about access: this is a long drive from Abidjan on deteriorating roads, permits and guided chimpanzee tracking must be arranged well in advance through the park authority, capacity is small, and accommodation is a basic camp. It is a trip for people who want the forest specifically, not a general-interest stop.
Most people stay 3 nights.