The second largest river in Indonesia, the mighty Mahakam is at once a major highway, a cultural tour and a wildlife-spotting expedition. It is also the only major river with public transport all the way into the heart of Borneo, making its 930km length entirely accessible.
Travelling up this jungle river is a journey in the fullest sense of the word. One heads away from the industrial centre of Samarinda and slips deeper and deeper into the jungle, and into Borneo’s past. A week later it is either time to start the difficult next stage of the Cross-Borneo Trek, or turn back. Along the way there is great variety, including the many boats that ply the river and local wildlife. Between Tanjung Isuy and Mancong our research trip encountered river otter, gold-ringed snake, python, proboscis monkey, macaque, kingfisher, monitor lizard, hornbill, stork, and an unidentified condor. There are many opportunities for exploration, from towns and longhouses to huge lakes, wetlands and other rivers. This is a place that rewards travellers with time on their hands and hence the ability to jump off the boat and wait for the next one, even if it means staying overnight.
As you continue upriver, tourist facilities recede – and what there is ain’t great. On the other hand, the Mahakam is one of those places where you shouldn’t worry too much about the details. Homestays materialise, ‘my brother’s boat’ appears, closed stores open. Westerners in particular will be greeted with legendary hospitality. Transport gets increasingly expensive the further upriver you go, due to the cost of lugging fuel that far, but everything else is dirt cheap, so a little money goes a long way.
In summary, this is off-the-beaten-track travel of the highest order. Outside the summer season, you’ll probably not see another foreigner your entire trip. There are few creature comforts, making health precautions particularly wise, but you also have the flexibility to turn back whenever you think you’ve seen enough (and the current downriver cuts the return journey in half). If you are comparing this with rivers elsewhere in Borneo, it is the defining experience.