The mountain rises to 1,752 metres — high enough that the air is cooler and mistier than the hot lowlands below. The slopes are covered in thick rainforest and open grassland, and tiny streams run down every side, feeding rivers that reach the Atlantic Ocean.
UNESCO gave Mount Nimba special protected status because it is home to hundreds of species found nowhere else on Earth. Scientists have discovered unique insects, frogs, bats and plants living only on this one mountain. It is like a living library of nature that took millions of years to write.
One of the most famous residents of Mount Nimba is the Nimba otter-shrew — a small, silky animal that looks like a tiny otter and lives along the mountain streams. Chimpanzees also make their home in the forest here, cracking nuts with stones and teaching their young to do the same.
The three countries that share the mountain have agreed to protect it together. Across the border, rangers and scientists co-operate so that the animals and plants can move freely through the forest without knowing anything about country lines — because, of course, they do not.