Otres is the long beach south of town that has historically been Sihanoukville's most attractive — a curve of pale sand backed by casuarina trees, with shallow water that stays warm year-round. It is divided into Otres 1 (the older, livelier strip with beach bars) and Otres 2 (further south, quieter, with low-key bungalow places).
Otres has been the part of Sihanoukville that survived the Chinese casino boom most intact, mainly because the developments stopped at the headland. The vibe is still backpacker-meets-yoga-retreat, with seafood barbecues at sunset and modest accommodation a few steps from the sand.