An hour's ferry from Sihanoukville, Sanloem is the quiet sibling island: a crescent of squeaky white sand at Saracen Bay, bioluminescent plankton on moonless nights and bungalows that cost less than a London round of drinks. Electricity can be part-time and Wi-Fi temperamental — treat that as the feature it is. November to May offers the calmest, clearest water.
Featured in Ten affordable tropical escapes that won't empty your savings · Tropical