Kantiang Bay, Koh Lanta, Krabi Province, Thailand.
Koh Lanta is far from a secret Thai island - in fact, it's one of the most popular in the Andaman Sea - yet I'm always surprised by just how little most visitors explore when they visit a new place. Most visitors locate themselves at the north of the island, near the main hive of Thai life, yet the south offers a great deal in the way of tranquility, respite, and relaxation. Not to mention some of the most stunning seascapes in the entire country. That last fact certainly does it for me.
Kantiang Bay is beautiful in its own right, and located near the remarkable Mu Koh Lanta National Marine Park on the southern tip of the island. Kantiang also makes a great base for exploring the Sea Gypsy village - if you're into that sort of thing. Which I am.
Fact; Chang Beer tastes better when you drink it on a rocky outcrop at sunset. True story.