Phnom Penh to Koh Rong: The Ferry, the Road, and Which Island

Sihanoukville is about 230 kilometres south-west of Phnom Penh and it is the only way to the islands - there is no ferry from the capital.

The expressway changed this route. Cambodia's first expressway runs Phnom Penh to Sihanoukville and cuts the drive substantially against the old National Road 4; buses and private cars both use it. Expect somewhere in the region of three to four hours door to door depending on the service and on getting clear of Phnom Penh, which is always the slow part.

Bus is cheap and frequent, several operators daily.

Private car from roughly USD 80-110, and worth it for two or more, particularly if you want to stop.

Flying is possible - Sihanoukville has a domestic airport - and is mainly useful on the way home rather than out.

The train. Cambodia's rehabilitated railway runs Phnom Penh to Sihanoukville a few days a week, via Kampot. It is slow and it is much more pleasant than the road, and it turns the journey into part of the trip. Check current days locally; the schedule moves.

Sihanoukville itself is a port and a construction site rather than a destination. The town went through an enormous, largely unfinished casino building boom and it is not somewhere to spend a night by choice. Time your arrival to catch a boat.

Boats leave from the ferry terminal in Sihanoukville throughout the day.

Fast ferry: 35 to 50 minutes to Koh Rong or Koh Rong Sanloem, depending on which pier you are heading for.

Wooden boats: about two and a half hours. Cheaper, slower, and a genuinely different experience if you have the time.

Tickets are bought at the terminal or in advance, and most are open-dated on the return leg, which matters because of the rule below.

⚠️ Ferries are weather-dependent and they do get cancelled, particularly from May to October. This is the single most important thing on this page:

Never plan an international flight for the morning after an island night. Come off the island the day before and sleep in Sihanoukville, Kampot or Phnom Penh. A cancelled boat is the one thing on a Cambodian itinerary that can genuinely strand you, and the airport is 20 to 24 km south of Phnom Penh on top of a four-hour drive.

Last sailings are in the late afternoon. If you are coming down from Kampot or Kep for the day, build the day backwards from the last boat, not forwards from lunch.

Koh Rong Sanloem is the quieter one and the right answer for most people. Saracen Bay is a long crescent of white sand with a strip of low-key resorts and guesthouses behind it, no roads to speak of, and genuinely little to do. Lazy Beach and M'Pai Bay on the other sides are quieter again.

Koh Rong is the larger island with more infrastructure, more nightlife and more people. Koh Touch is the party end; the north and east beaches - Long Set, Sok San, Palm Beach - are much calmer and are where most of the better accommodation has gone.

What to actually do: not much, which is the point after a hard-working Cambodian itinerary. Bioluminescent plankton after dark on a moonless night, away from beach lighting, is the local speciality and it is real. Snorkelling trips run from both islands and are pleasant rather than world-class - the reefs took a beating and are recovering unevenly.

What to expect and not be surprised by: power and water are limited on both islands, many places run generators with set hours, wifi is variable to absent, and ATMs are scarce or non-existent. Take cash in small US dollars for the whole stay.

Sandflies on some beaches are worse than mosquitoes. Repellent, and do not lie directly on the sand at dusk.

Be honest about this one: Cambodia's islands are good, and they are not why anyone books Cambodia. Thailand's are better and easier. What these have is emptiness and price.

They need ten days. Our ten-day itinerary is the shortest that reaches them without wrecking what comes before - four nights Siem Reap, one Battambang, two Phnom Penh, two on the Kampot pepper coast, one island.

At eight or nine days, skip them. A second night in Kampot or a fifth temple day gives you more. The eight-day route stops at the coast for exactly that reason.

Two island nights beat one. One night means arriving in the afternoon and leaving in the morning, which is a boat trip rather than a stay.

The natural route is Phnom Penh → Kampot and Kep → Sihanoukville → island, which strings the whole south together and never doubles back. Coming from Kampot the ferry terminal is about two to two and a half hours.

Season. November to April for the islands - calm seas, reliable boats. May to October is when sailings get cancelled, which is the same window that makes the temples green and cheap. The country does not give you both.