Koh Lipe is a tiny, walkable island in Thailand's far south, on the edge of the Adang-Rawi group of Tarutao National Marine Park. From a single beach-town base you can snorkel and freedive shallow house reefs, then hop into a longtail or speedboat for soft-coral gardens, granite boulder slopes, walls, and offshore pinnacles like Stonehenge and 8 Mile Rock. Water stays warm most of the year (often around 28°C), so a rashguard or 3mm suit covers many divers. The prime window is the dry season (roughly November to April) when seas are calmer and boats run reliably. Monsoon months can bring wind, rain, and partial marine-park closures, so plan day trips carefully and expect fewer crossings. Koh Lipe is also an easy add-on for travelers coming via Langkawi, Malaysia, turning a beach holiday into a compact dive-and-snorkel safari.