The Kinabatangan River is a brown, muddy vein with endless tributaries flowing from its source in the Witta Range, the mountainous east of Sabah, wandering 563km to a mangrove swamp in the delta of the Sulu Sea. Over the years, erosion and soil deposits influenced its course, creating 20 oxbow lakes in the lower regions where twitterers are aghast at the large variety of birds winging through the sky—hornbills, hawks, falcons, herons, and jewel-colored kingfishers. Due to palm oil plantations encroaching on the forest, the jungle creatures have become trapped along the narrow swathe of land along the riverbank, where the water is swarming with crocodiles and fish. Snakes and lizards sun themselves on tree branches while immense dragonflies and beautiful butterflies flit through the jungle's foliage. The river has become a wildlife-spotting hotspot.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - Kinabatangan River

In the 7th Century, Malaysia's second-longest river became home to Chinese traders hawking rattan, ivory, beeswax, and edible-nest swiftlet. Today, its riverbanks are splattered with rustic homes of indigenous people known as Orang Sungei, the Malaysian word for 'River People,' living in small communities and surviving on fishing and farming while sourcing their needs of food, medicine, firewood, and building materials from the surrounding forest. Simple wooden boats litter the foreshore of their villages where white egrets cast rippling reflections on the river's surface, fat cows graze on the grassy banks, and proboscis monkeys dangle in treetops like Christmas decorations.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - River Bank with Boats

Staying on the river in a lodge depends on your budget or whether you are into the eco-warrior world of rustic huts with few amenities—think mattress with a mozzie net and shared ablutionary facilities—basically backpacking in an untamed landscape. For those that like to be pampered no matter where they are—Sukau Rainforest Lodge (David Attenborough and National Geographic have slept here), Kinabatangan River Lodge, and Abai Jungle Lodge will give you a sweet night, knowledgeable river guides, and the opportunity to delve into the river wilderness in comfort.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - Orangutan

Staying at a river lodge will give you a front row seat to this natural world. Orangutans and monkeys herald their proximity with the shaking of trees as they hilariously swing through the rainforest nearby at any hour of the day or night. In fact, Sukau Rainforest Lodge has its own local wild orangutan named Lucy, who tends to poke her nose around the lodge, with or without her kids in tow. Each humid night after the sun has set in a blaze of crimson, the air is saturated with a jungle orchestra playing an opera of thousands of squawking, grunting, buzzing, honking, shrieking, and scuttling critters. The complete blackness twinkles when the fireflies come out to play in a magical dance.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - Crocodile

The jungle theatrics continue in the wee hours of the morning as you struggle to clamber onto a boat before the sun has shown its face. The water is glassy, laden with sediment, and mist drapes low over its sepia-colored surface. The muddy banks are exposed where a crocodile may be lazing, proboscis monkeys begin to stir in their lofty tree heights, and a rhinoceros hornbill's orange and red casque distinctly flashes amidst the lush green foliage. Intermittently, palms litter the riverside in contrast to the dense jungle covering of massive weeping figs dipping their roots haphazardly into the murky depths. Strangler figs weave and cling to limestone cliff faces where swiftlet birds hover over their nests in crevices.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - Boats

As the sun slowly rises, the jungle becomes a unique wonderland of animal activity. Long-tailed and stump-tailed Macaques get busy scrounging breakfast, orangutans lurk in the canopy, and an Asian Water Monitor lizard slinks along a tree branch jutting out into one of the many narrow tributaries. If you are lucky, sighting a pygmy elephant will leave you gobsmacked, especially if a muddy bath for them is involved. Langurs and gibbons haunt treetops, and the shy creatures that are rarely seen—deer, clouded leopards, sun bears, slow loris, flying lemurs, civets, and tarsiers—become the dinner talk of gloating lodge guests lugging around powerful binoculars.

A Gift to the Earth - The Kinabatangan River - Sabah, Borneo - The Wise Traveller - Boat

Despite being declared as Sabah's 'gift to the earth' and gazetted as a sanctuary by the government in 2005, the Kinabatangan River area still faces many conservation issues. Along the riverbanks are a few research and NGO campsites, some of which you can stay at. Many are lonely and simple outposts of hardy souls amidst one of the world's richest ecosystems that includes some species only endemic to the region—10 primate species, over 250 different bird species, 90 fish species, 20 reptile species, and a wondrous 1056 identified plants. Recently, researchers stumbled upon a mystery monkey species that appears to be a rare hybrid between a silvery langur and a proboscis monkey, which can occur when two related species share the same habitat with limited space and mating opportunities. This unique river area is adapting and changing.

Cruising the Kinabatangan River is the quintessential experience of heading into the pulsating heart of Borneo.

Gail Palethorpe, a self proclaimed Australian gypsy, is a freelance writer, photographer and eternal traveller. Check out her website Gail Palethorpe Photography and her Shutterstock profile.