Perhaps the major frustration of travel in eastern Cambodia is the amount of backtracking required to reach both Banlung and Sen Monorom. That’s the bad news. The good news – unless you’re an environmentalist – is that a road between the two is currently under construction (largely, it’s said, to allow easier extraction of the region’s valuable timber and other natural resources). Due to be finished by around 2015, the new Banlung–Sen Monorom highway will allow visitors to follow a single, far quicker, loop through Rattanakiri and Mondulkiri and save a couple of days’ travel without any of the to-ing and fro-ing which getting to both of the destinations currently involves.
Pending the construction of the road, the journey is still doable in the dry season, but no picnic (and in the wet season forget it). The first 35km from Banlung is along good, recently upgraded road to Lumphat. Beyond here you enter thick forest, following small, confusing and badly rutted tracks for 55km before emerging from the woods at Kaoh Nhek, from where it’s another 93km to Sen Monorom along a good graded track. Motos can be rented in Banlung and Sen Monorom to make the gruelling 8hr journey for around $80. Alternatively you could hire a 4WD for around $250, well worth the cost if you can get a group of four or five people together.