Four Seasons Koh Samui
This is easily one of the most spectacular hotels in the world. Its natural surroundings are breathtaking: turquoise waters, tall palm trees, and not a hint of development in the immediate area. Rooms, too, are impeccably designed, with state-of-the-art amenities. Most have private infinity pools; there's another pool with a bar down by the water if you want to be closer to the action. The only downside is that you'll never want to leave the hotel and explore the island.