Not to be confused with the other Koh Thian, a couple of kilometres away, which is an island a lot of people will visit on a snorkelling trip. Whereas this island no-one goes to specifically. Adjacent to Koh Klang, just off the northern shores of Koh Rang. Nothing noteworthy, but it adds to the scenery.
Worth Visiting? No. Clear water but not an obvious snorkelling spot, no buoys in the vicinity so it seems other people agree on this too.