Tucked away in the remotest corner of Sabah, Maliau Basin is perhaps that state's last and greatest untouched wilderness.
The basin is a ring of mountains 22 km in diameter, with just one outlet - Sungai (River) Maliau, and wholly protected as a 59,000-ha Conservation Area.
The Basin has no roads and has never been logged; access is by walking trails on overnight treks only.
It is said that no human entered the Basin until the 1980s. Perhaps some indigenous people did, but if so there's no record of it.

We stayed four days at the Basin's Field Centre which is just outside the Basin and Conservation Area.
After a month exploring (mainly) the forests and wildlife of northern Borneo, this was our final destination before heading home.