North Sentinel Island
Bay of Bengal
Island appeal: Despite its cerulean shores and stunning coral reefs, this dot of land in the Indian Ocean is the holy grail of inaccessible islands. In fact, the hunter-gatherer inhabitants have resisted contact with the outside world for 60,000 years and continue to drive away governments, researchers, and movie directors with bows, arrows, and spears. Not much is known about the Sentinelese, except that they're hardcore adherents to the Paleo diet. No carbs and we'd be throwing spears too.
Why it's so secret: The Sentinelese have the hospitality of frat boys during rush. They greeted government officials with gestures of defecating and a documentary film director with a 8ft arrow to the thigh. Two fisherman who washed up on island met an early demise and were buried under the sand. Still, it's really beautiful and you should visit.