The canopy walkway is the single best structure in the reserve, a suspended walkway high in the crowns where hornbills, gibbons and mixed flocks pass at eye level. Dawn here is the highlight of most visits.

The trail network from the field centre and the lodge holds orangutan — wild, unprovisioned and usually detected by falling debris rather than sight — red leaf monkeys, gibbons calling at first light, bearded pig and mouse deer.

The access road at night is the mammal-watching drive: civets, flying squirrels gliding through the spotlight, slow loris, and a genuine if slim chance of clouded leopard, which is seen here more than almost anywhere.

The Segama river and its tributaries add otters, kingfishers and the chance of elephants coming down to drink — the pygmy elephant herds move through the valley unpredictably.

The drier months from March to October make the trails easier, but rain is constant in any month and leeches are a fact of life.

Practicalities

Access is from Lahad Datu by a two- to three-hour drive on a logging road, and there are two options: the Borneo Rainforest Lodge, which is comfortable and expensive, or the Danum Valley Field Centre, which is a working research station with basic accommodation and far lower prices.

Both need booking in advance and neither permits casual arrival — this is a conservation area with controlled access, not a national park. Bring proper boots, leech socks and a torch worth using.