Sabah's longest river springs up high in the Crocker Range and flows 560km before spilling out into the Sulu Sea. The lush tropical forests downriver are teeming with rare and unusual wildlife, including orangutans, gibbons, proboscis monkeys, flying foxes, the adorable slow loris and the world's smallest elephants, as well as reptiles, birds and insects found nowhere else in the world. Tours to this region usually last two or three days, offering a combination of peaceful river trips, a trek to the wildlife-rich Ox Bow Lake, eerie night hikes to spot strange nocturnal creatures and dawn cruises to catch glimpses of waking primates.

The abundance of creatures and the sensation of being truly in the wilderness combined with the relaxing nature of the cruises and gentle hikes mean the Kinabatangan River is a holiday highlight for many, even on days when the wildlife appears to be hiding. The knowledge that these animals are wild and following natural behaviour patterns makes even a fleeting glimpse feel particularly special - so bring your binoculars for a closer peek into their world.

Once safely back in Kinabalu National Park, you can soak your achey legs in the hot sulphur springs, and marvel at the otherworldly flora, including the rafflesia - the world's largest bloom, over 500 species of orchids and sinister, carnivorous pitcher plants.

Sabah has over 30 ethnic cultures - including the Bajau "sea gypsies", many of whom still live on boats; the fierce Murut, once renowned for their headhunting and blowpipe skills; and the animistic Kadazandusun, who cultivate rice paddies and honour the rice spirits to ensure a good harvest.

There are numerous things to do in Sabah for those who want to meet its fascinating, friendly people. The excellent MESCOT community tourism organisation offers homestays along the Kinabatangan River; guests can savour local food and learn how it is cooked, take part in farm activities and play village sports with the local community. Alternatively, learn about the life of a tea picker at Sabah Tea Plantation, and spend the night there in a traditional Rungus longhouse - decorated with exhibits from seven of Borneo's tribal groups.

This vast sanctuary gives orphaned, injured and captured orangutans a second chance at life in the wild. Babies are paired with adults, and taught to climb, forage, build nests and even use tools. This is the classic thing to do in Sabah - so come for the afternoon feeding session to avoid the worst of the crowds - and know that your visit supports the continued conservation of these fascinating apes.