Central Island is no extinct curiosity. Its youngest lavas and ash may date to the Holocene, geologically yesterday, and the volcano remains restless. Fumaroles vent along the rim of the central crater, and visitors in the 1930s watched sprays of yellow sulfur jet from the ground. In 1974, observers on the distant mainland saw intense emissions of molten sulfur and towering clouds of steam pour off the island. The land here is dominantly basaltic, its high point reaching 550 meters, and an east-west chain of explosion craters slices across the eastern flank. Beneath the lake's surface, more cones and lava plugs lurk, drowned remnants of a fire that has not gone out.

The island's strangest feature is water held inside water. Three of its craters have filled to become lakes in their own right, each given a name for what lives or gathers there. Crocodile Lake and Flamingo Lake fill the two largest craters, basins nearly a kilometer wide and roughly 80 meters deep, their floors sitting close to sea level even as they perch inside an island in a lake. A third, Tilapia Lake, completes the set. Each crater lake has evolved its own small ecosystem, isolated from its neighbors by walls of volcanic rock. Stand on a rim and you can look down into one colored pool while the vast green expanse of Turkana stretches beyond.

Each April and May, the shores of those crater lakes become one of Africa's great reptilian spectacles. Female crocodiles haul out and bury their eggs deep in the warm sand, beyond the reach of monitor lizards and raptors that would dig them up. When the time comes, the hatchlings begin squeaking from inside their buried shells. The sound carries, and the mothers come scrambling to excavate their young and carry them gently down to the water in their jaws. The lake's crocodile population, estimated in the thousands, descends from a lineage that has barely changed in well over a hundred million years. Central Island is their nursery, undisturbed and almost entirely without people.

Crocodiles are only the loudest residents. The island and its lakes draw an extraordinary density of birds, with dozens of water-bird species recorded on and around it. Lesser flamingos wade the shallows of the volcanic lakes, tinting the water pink at the edges. Goliath herons and African skimmers breed here, and each spring the island fills with European migrants pausing on their long journey north. For a speck of rock in a desert lake, the variety of life crowding its shores is startling, a reminder that even the most forbidding landscapes can become essential waypoints.

Today the whole island is Central Island National Park, managed by the Kenya Wildlife Service and part of the Lake Turkana National Parks World Heritage Site. There are no towns, no roads, no permanent inhabitants, only the volcano, the crocodiles, the birds, and the wind off the lake. Reaching it means a boat across open and often rough water from the Turkana shore, and the reward is a place that feels genuinely primeval. To climb a crater rim here, with steam venting somewhere behind you and hatchlings calling from the sand below, is to stand inside a landscape still being made.