Kahuzi-Biéga National Park

Listen first. Water drips from leaf to leaf above you. Somewhere uphill, a branch snaps under real weight. The air is cool and wet, and it smells of moss, crushed stems and damp earth. Under your boots the trail is soft and dark, and it gives a little with each step. This is the montane forest of Kahuzi-Biéga, in the South Kivu province of the Democratic Republic of the Congo. For many visitors, the first thing they notice is how quiet it is.

The park takes its name from two old volcanoes, Mount Kahuzi and Mount Biéga. Both are extinct, and both rise above the forest to the west of Lake Kivu. Mount Kahuzi is the taller of the two. Its summit stands at a little over 3,300 metres, which makes it the highest point in the park. On a clear morning the peaks show their rounded shoulders above the trees. On most mornings, though, they hide inside the cloud.

Here is the first surprise. Most of this park is not mountain at all. A small highland sector sits near the city of Bukavu, and this is where most visitors walk. But a much larger lowland sector spreads west into the Congo Basin, the great rainforest at the centre of Africa. A narrow corridor of land links the two. Together they cover thousands of square kilometres. Very few outsiders ever see the lowland side.

And why do people come? For one animal above all — the eastern lowland gorilla, also called Grauer's gorilla. It is the largest of all the gorillas. A grown male, a silverback, is named for the band of pale grey hair across his back. Grauer's gorillas live only in the eastern Congo. They are listed as critically endangered, and this park is one of the most important places left for them.

The story of the gorillas here is also a story about people. In the decades around the park's creation, conservationists began a slow process called habituation. Rangers and trackers visited the same gorilla families day after day, for months and years. Over time, the gorillas learned that these humans were not a threat. That patient work is why you can stand near a wild family today. The gorillas were never trained. They simply learned to accept a quiet human presence.

Kahuzi-Biéga became a national park in 1970. Ten years later, in 1980, UNESCO added it to the World Heritage List — the international list of places with value for all of humanity. But in 1997, the park was moved onto the List of World Heritage in Danger. Wars and armed groups in the eastern Congo brought poaching, mining and logging deep into the forest. Rangers have worked through these years, often at great personal risk, and some have lost their lives protecting it.

There is a harder part of the story too, and it is worth knowing. The Batwa, a forest people who lived and hunted in these hills, were moved out of the land when the park was created. Many families lost their homes and their way of life. That loss is still felt, and the relationship between the park and the Batwa remains a live and difficult question today. A forest like this one is never only about animals.

Most gorilla treks begin at the Tshivanga visitor centre, in the highland sector. Before you leave, rangers give a briefing. They explain how to move, how to stand, and what to do if a gorilla comes close. Then trackers go ahead to find the family. The walk can be short, or it can take hours. It depends entirely on where the gorillas chose to sleep the night before.

Now look around you as you walk. The forest changes with height. Lower down, the trees grow tall and close, with ferns and vines filling every gap. Higher up, you enter stands of mountain bamboo. The stems are smooth and segmented, and they knock softly against each other in the wind. Here is the second surprise — young bamboo shoots are a favourite gorilla food. Where you see broken and chewed stems on the ground, a family may have eaten there very recently.

The trackers read these signs for you. Flattened plants show where the gorillas walked. Fresh droppings show how close they are. Loose piles of leaves and branches on the ground are night nests. Each gorilla builds a new one every evening, and leaves it behind in the morning. Once you start to notice these signs, the forest looks less like a wall of green. It begins to look like a map.

When you reach the family, the rules matter. Keep your voice low. Keep the distance the rangers ask for. Wear a mask if they give you one, because gorillas can catch human illnesses, even a common cold. Your time with them is short — usually around an hour. Watch how the young ones wrestle and tumble. Watch how the silverback sits apart, eating calmly, and how the others keep an eye on him. Watch his hands. They are so much like your own.

The gorillas are not the only residents. Chimpanzees live in this forest as well, though they are harder to see. Monkeys move through the high branches, and the bird life is rich, with species found nowhere outside this part of Africa. In the lowland sector, the forest holds even more, including forest elephants. Much of the wildlife you will only hear. A call far away, a rustle in the leaves, and then nothing.

Before you go, take one more moment where you stand. Feel the cool air on your face. Look at the moss on the nearest trunk, and the light coming down through the canopy in narrow grey beams. This forest has survived a great deal, and its future is still uncertain. As you walk back along the trail, listen again for that snapping branch. Somewhere close by, a family is still eating, still resting, still going on with its day.