On the west side of the island is Koh Rong's finest beach, a 7km, almost empty stretch of drop-dead-gorgeous white sand. Sok San village at the northern end has a cluster of local eating spots and simple guesthouses. Unfortunately the beach around the village is quite dirty; walk south for cleaner waters. Two ferry companies service Sok San village in high season (November to May). You can walk from Koh Tuch to Sok San's south end via the jungle trail.
You can also reach the village fairly easily by moto from Kuh Tuch (US$15). Developers, not surprisingly, have their eye on this sensational sunset-facing strip. A luxury resort has opened on the beach's south end and there's another one in the works.