This small speck of an island, its hill covered in lush vegetation, has a sordid 500-year history as a pirate haven, which only came to an end during the reunification in 1975. Today the inhabitants make their living from the sea. A paved motorbike trail circles the island; you can hike up to the hill temple and visit the tranquil beach, and if you come with a Vietnamese speaker, you can arrange to go out with the fishermen.
Besides the 100 or so inhabitants who reside in the four small, scrappy fishing villages, there's an army base on top of the hill, keeping a vigilant eye out for potential invaders from Cambodia. Rumours of pirate treasure have circulated for years, and in 1983 the army promptly expelled from Vietnam a couple of foreign treasure-seekers who arrived illegally by boat from Cambodia, equipped with metal detectors.
There's limited electricity until 10pm, after which the only light comes from candles and boat lights. Going out on a fishing boat at night, you may see the sparkly shapes of fish shoot through the water, thanks to the phosphoresence phenomenon.
It's reachable either by green cargo boat (40,000d, 1½ hours) that departs Ha Tien at 2.30pm, returning from the island at 9am, or by passenger boat (100,000d, 1¼ hours), departing Ha Tien at 9am and returning at 4pm. The passenger boat sometimes doesn't run; otherwise it's possible to borrow a bicycle in Ha Tien and pop over for the day. Otherwise, there are a couple of very simple homestays (60,000d per room) and if you buy some fish or crabs from the fishermen, your hosts can cook you dinner.
