Mount Karthala

We left the village of Boboni at four in the morning, by torchlight, through the smell of cook-smoke and wet earth. My guide, a man named Saïd who had done the climb perhaps a hundred times and showed no particular excitement about doing it again, carried a machete and a bag of rice and moved through the darkness at a pace I could barely maintain on a good day. The forest closed around us immediately — not the thin, transparent forest of temperate mountains but something truly opaque, the branches overhead making a ceiling, the undergrowth pressing in from both sides, moisture dripping from things unseen. Within an hour I had lost any sense of direction other than up.

The cloud forest of Karthala is not like the forests lower on Grande Comore. At altitude, the vegetation turns strange — tree heathers with trunks thick as a man’s torso, giant ferns, mosses that cover everything with a soft green pressure. The endemic Comoros olive pigeon calls from somewhere in the canopy, a sound like someone blowing across the mouth of a bottle. The path, where it existed as a distinct thing, was knee-deep in mud from the previous night’s rain. I fell twice. Saïd did not fall once. When we broke above the cloud line around 1,800 metres, the sudden light was almost shocking — the forest below us a white sea of cloud, the summit cone still rising ahead, dark and austere. Nothing about it looked welcoming. I was completely in love with it.

The final approach to the caldera rim is through a zone of sulphur vents where steam rises from cracks in the black rock and the air smells of something between rotten eggs and the inside of a struck match. My eyes watered continuously. The rock underfoot was crumbly and unstable in places — Karthala erupts with regularity, the last significant eruption in 2007, and the mountain does not pretend to be dormant. Standing at the rim of the caldera, looking down into a space roughly four kilometres wide, I had the particular vertiginous sensation of standing on something that was actively, unhurriedly working. The silence was immense but not peaceful. It had a quality of held breath.

The descent was harder on the knees than the ascent but faster — we were back in Boboni by mid-afternoon, sliding down the same mud I had struggled up in the dark. That evening in Moroni, eating rice and coconut fish on a plastic table, I kept looking at the mountain’s silhouette against the last light. It did not look any more or less remarkable than it had the day before. It just looked like the mountain it was — enormous, patient, entirely uninterested in what I thought of it. I respected that enormously.

When to go: June through September is the driest and most reliable window for the climb — cloud cover is still unpredictable, but rain is less constant and the paths are somewhat less treacherous. The hike to the caldera rim takes seven to nine hours round trip from the trailhead near Boboni; an overnight on the rim is possible and extraordinary, weather permitting. Always hire a local guide — the forest path is genuinely difficult to follow and conditions change quickly.