Bwindi means 'impenetrable' - the forest is so thick with vines, ferns and giant trees that you have to push your way through, foot by foot. The trees drip with mist most mornings. Walking inside Bwindi feels a bit like being inside a green cloud.
An adult male mountain gorilla is called a silverback because of the silvery fur that grows on his back as he gets older. He weighs around 200 kilograms - that is twice as heavy as an adult person. Even though they are huge and strong, silverbacks are calm. They lead their families gently, mostly by deciding where to walk each day and where to sleep at night.
Mountain gorilla families have around 10 to 20 members - the silverback, several mothers, and their children of different ages. Baby gorillas play almost exactly like human toddlers: they chase each other, climb on their parents, and giggle. Mothers carry their babies on their tummies for the first few months, then on their backs.
Each morning, the family wakes up, slowly munches their way through leaves and bamboo shoots, then naps in the afternoon, then walks a little further before bed. They build a new bed of leaves every single night - they never sleep in the same place twice. Scientists in Uganda have been studying these families for over 30 years.