Long Iram village on the Mahakam River, Kalimantan

Cross Borneo Trek

The Muller Mountains sit almost smack bang in the middle of Borneo, straddling the provincial borders between West, Central and East Kalimantan. A relatively small range with a high point of only 1,700m, geographically the Muller’s aren’t particularly significant other than being the watershed for two of Borneo’s mightiest rivers. To the west, the Muller’s drain into the Kapuas River and to the east the Mahakam River, and it is this aspect that is of most interest to those travellers seeking a once in a lifetime adventure. By trekking across the Muller Mountains from one side to the other, it’s possible to complete an east-west cross Borneo traverse.

Upper Mahakam River in the heart of Kalimantan (Borneo)To do so requires journeying the full length of the Kapuas River from Pontianak on the West Kalimantan coast to the tiny, remote Dayak village of Tanjung Lokan (4-7 days), trekking across the Muller Mountains to Tiong Ohang village on the upper reaches of the Mahakam River (5-7 days) then proceeding downriver to Samarinda (4-5 days) on the East Kalimantan coast. Or vice versa.

Crossing the Muller Mountains is not a trek to be taken likely. It’s a hot and steamy hike along a narrow jungle path with frequent water crossings (some quite deep), leaches and only a basic camp to look forward to at the end of the day. It goes without saying that a high level of fitness and preparedness is required. A guide is essential. Almost in its entirety, the route passes through dense jungle with no visual references. Without an experienced local guide, the chances of getting lost are high.

Cross Borneo trekking is not for the faint heartedDue to the nature of the trek, there’s no guarantee of picking up a local guide or porters at short notice at either trail head. Therefore, this is one of those occasions where organising a guide in advance from Pontianak or Samarinda is highly recommended. Contact one of the many tour and travel agents in either city. Alternatively, there are now several tour companies (some online) offering organised cross Borneo tours. If you like the sound of this option but money’s tight, consider engaging them for the Muller Mountain crossing only and undertaking the river journey’s independently.

Pontianak on the West Kalimantan coast to Samarinda on the east coast (or vice versa)
West/central/east Kalimantan
Up to 3 weeks
Get there
Starting point in the west is Pontianak.  Samarinda in the east
Need to know
Arrange guides in advance at Pontianak or Samarinda or book a tour.