The only resort on Koh Thmei is a gem, with tidy bungalows that use solar panels and biofuel for electricity. The resort sits on a private beach, and you can easily walk to more. Or go sea-kayaking, snorkelling or hiking. It's open year-round, with table football and board games to keep you entertained when it rains.
Excellent Khmer meals (US$6) and a full bar. The resort is right on the maritime border with Vietnam, with prime views to nearby Phu Quoc Island. The only available cell signal is Vietnamese. Electricity runs from 6.30am to 11pm.
It's an extremely atmospheric one-hour boat ride from the mainland fishing village of Koh Kchhang in the resort's private boat (US$8.50 per person one-way). We spotted Irrawaddy dolphins on our most recent trip. Management can arrange transport to Koh Kchhang from Sihanoukville, Kampot or the Sihanoukville airport.