Koh Kong sits at the Cambodian end of the Cham Yeam border crossing with Thailand, 9 kilometres from Hat Lek on the Thai side. From Koh Chang or Trat, a minivan to the border plus a tuk-tuk in town takes around three hours.
From inside Cambodia, the road south from Phnom Penh (about 6 hours by bus) and the road from Sihanoukville (about 4 hours) both arrive at the river bridge. There are no scheduled flights — the small Koh Kong airport handles charters and military traffic only.