Koh Rong Island, along with Koh Rong Samloem Island next door, are Cambodia's largest, most popular dive sites. A half hour by speed boat from SihanoukVille, and 2 hours by regular dive boat, both islands offer an outstanding diversity of marine life. Not too much of the bigger fish, but much more variety than found elsewhere in Asia.
Several Dive shops operate right on the Islands, some have bungalows right on the islands, or come straight from SihanoukVille for day trips or overnight trips.