2. North Sentinel Island – India
The North Sentinel Island is a remote island under Indian territory. Typically, a tourist would need a visa from Indian authorities to visit the surrounding islands but in this case, you can give up all hope of getting a visa. The Indian government does not allow anyone for any reason to travel near North Sentinel as it is home to the Sentinelese, an isolated and uncontactable tribe.
Unfortunately in 2019, a missionary, John Allen Chau, illegally ventured onto the island in the hopes of converting the Sentinelese to Christianity. He was confronted with aggression in his attempts to make contact but persevered in getting close to the tribe, however, he has never been seen or heard of since.