Tanjung Puting

Everyone goes to the Malaysian side of Borneo for orangutans, and they are right to — Sepilok is excellent. But the encounter I keep returning to happened on the Indonesian side, on a slow brown river in Central Kalimantan, from the deck of a boat that moved at roughly the speed of a thoughtful pedestrian. Tanjung Puting is reached from Kumai, a scruffy port town that smells of salt and two-stroke fuel, and the journey in is the entire point. You don’t visit Tanjung Puting so much as you marinate in it.

The klotok and the river

A klotok is a wooden river boat, maybe twelve metres long, with a thumping single-cylinder engine downstairs and a flat open deck upstairs where you live for two or three days. Ours had a cook named Ibu Sari who produced extraordinary meals from a galley the size of a wardrobe, a captain who knew every snag and sandbar, and a guide who could spot a sleeping kingfisher at forty metres. The Sekonyer River is the colour of strong tea, stained by tannins from the peat swamp, and as you push upstream the nipa palms close in until the channel narrows to a green tunnel and the proboscis monkeys start appearing in the riverside trees, the males with their absurd pendulous noses and pot bellies, leaping between branches with a crash and a splash.

Lia and I slept on mattresses on the roof under a mosquito net, and I am not exaggerating when I say it was one of the best nights of the whole trip. The engine cuts out. The river goes silent except for insects and the occasional heavy splash of something — a monitor lizard, a fish, a falling fruit. The stars over Kalimantan are uncountable. At some point in the night I woke because the boat shifted, and there, in the grey pre-dawn, a long-armed silhouette was sitting in a tree directly above us, perfectly still, watching the strange humans asleep on the floating thing.

Camp Leakey and the feeding platforms

The reason the park exists in its current form is Biruté Galdikas, who set up Camp Leakey in 1971 and has been studying and rehabilitating orangutans here ever since — the longest continuous study of any wild mammal. At the feeding platforms, rangers put out bananas in the late morning, and the rehabilitated and semi-wild orangutans come in from the forest to eat. It is managed and it is not wilderness, and I went in slightly cynical about the whole arrangement. Then a huge dominant male called Tom came down the path on his knuckles, two hundred pounds of deliberate muscle, and every human on the boardwalk went silent and small. He sat ten metres away and ate methodically and ignored us entirely, which felt exactly correct.

The walk back to the boat from Camp Leakey passes through swamp forest on a boardwalk where wild bearded pigs root around and gibbons sing somewhere overhead, that liquid whooping call that carries for kilometres. By the third day on the river I had stopped checking my phone, which had no signal anyway, and had fallen into the rhythm of the boat — eat, watch the bank, doze, watch the bank, eat. It is the rare wildlife destination that slows you down rather than speeding you up.

When to go

The dry season, roughly June to September, makes deck-sleeping pleasant and keeps the worst of the mosquitoes down, though they are never truly absent — bring repellent and long sleeves. Book a klotok with a reputable operator out of Kumai or Pangkalan Bun; a two-night, three-day trip is the sweet spot. Fly into Pangkalan Bun via Semarang or Surabaya. Bring more memory cards than you think you need, and a head torch for the night.