The Volcanoes National Park traces its lineage to 1925, when Belgium's King Albert I created the Albert National Park -- the first protected area on the African continent. Its primary purpose was to shield the mountain gorillas of the Virunga range from hunters. In 1929, the park expanded to encompass the Rwandan volcanoes, covering over 8,000 square kilometers across what was then the Belgian Congo. When the Congo gained independence in 1960, the Albert National Park split in two: Virunga National Park on the Congolese side and Volcanoes National Park in Rwanda. The Rwandan park, now roughly 160 square kilometers, protects the steep, forested slopes of five of the eight Virunga volcanoes -- Karisimbi, Bisoke, Muhabura, Gahinga, and Sabyinyo.

Gorilla trekking here begins with organized chaos. At seven in the morning, visitors gather at the park headquarters near Kinigi for registration, tea, and sometimes a traditional dance performance. Guides sort groups by fitness level and assign each a gorilla family to visit. Then the driving begins -- twenty to forty-five minutes on roads that test the definition of the word -- to a trailhead somewhere on the park's edge. The walk from there crosses terraced farmland before reaching the park boundary, marked by a stone wall. Beyond it, the terrain changes. Bamboo thickets close in. The trail steepens and muddies. Trackers who left before dawn radio back coordinates. When you finally encounter the gorillas -- sometimes after an hour of hiking, sometimes after five -- you have sixty minutes. No more. The silverback may glance at you with what looks like bored indifference, or he may charge to within a few meters, a bluff that stops hearts. The one-hour limit exists because every human contact carries the risk of disease transmission to animals that share 98 percent of our DNA.

The Virunga volcanoes are not merely backdrop. Karisimbi, the tallest at 4,507 meters, offers a two-day climb through bamboo, then Hagenia forest, then alpine meadow, before reaching a summit that can drop below freezing. Bisoke's crater lake, shimmering in the thin air at 3,711 meters, is reachable in a challenging single-day push. Mount Sabyinyo, whose name means "old man's teeth" in Kinyarwanda, has a jagged summit ridge where hikers can stand at the meeting point of three nations -- Rwanda, Uganda, and the Democratic Republic of Congo. These are not technical climbs, but they are demanding: steep, muddy, and unpredictable in weather. The park's montane ecosystems shift visibly with altitude, from dense bamboo at the base through mossy Hagenia-Hypericum woodland to open heath studded with giant lobelias near the summits.

Dian Fossey's grave sits near her former Karisoke Research Center, high on the saddle between Karisimbi and Bisoke. She is buried beside Digit, the silverback whose killing by poachers in 1977 transformed her from researcher into activist. The $75 trek to her grave is quieter than the gorilla treks -- fewer visitors, longer walks, and a solitude that Fossey herself would have preferred. Near the park headquarters, the Ellen DeGeneres Campus of the Dian Fossey Gorilla Fund presents the science behind gorilla conservation through indoor and outdoor exhibits, with views of the volcanic chain from its terrace. Fossey's methods were controversial -- she burned poacher camps and held captives -- but her single-mindedness helped buy time for a species that had none to spare.

The mountain gorillas share these forests with another primate found nowhere else on Earth. Golden monkeys, with their bright orange-gold patches against dark fur, live in the bamboo zone and are tracked on separate permits far less expensive than the gorilla treks. They move fast, leaping between bamboo stalks in groups of up to a hundred, and photographing them requires patience and luck. Beyond the primates, the park's montane forests support over 170 bird species, and the volcanic terrain itself -- old lava flows, crater swamps, alpine bogs -- creates habitats unlike anything else in East Africa. The air is thin here, the equatorial sun deceptively strong, and the rain comes without warning. Visitors shiver more than they sweat, just as Fossey described.