The Andaman Archipelago is in the Indian Ocean's Bay of Bengal. It lies in between Burma and Indonesia and contains about 200 islands, and in it, there's a little island, a little off to the west of the bulk of others, called North Sentinel Island. It's about the size of Manhattan and has between 50 and 400 inhabitants. Nobody knows for sure. That's because that island is totally unexplored. "How can this be?" you might ask, considering that people live there. Well, the island's plenty accessible, but the Sentinelese are notoriously resistant to any visitors whatsoever.
If the island is anything like the other islands in the region, it's home to unique flora and fauna. Most of the Andaman islands contain over 2,000 species of plants, 1,300 of which are not found on the mainland in India. We don't know much more, except that a tsunami in 2004 changed the geography of the island, and that the lagoon is eroded. As of 2015, fishers looking for sea cucumbers (a delicacy in China) were trying to encroach on the waters around North Sentinel, but it would be disastrous for the people there if the fishers could come onto the island. The Sentinelese have not built any immunity to diseases modern people could carry to them, and interference could well wipe them out, which would kind of be a shame.
While it is all well and good to want to explore the unexplored, we shouldn't, like, wipe out indigenous and ancient cultures. And, for that matter, it might be good if we didn't junk up Mount Everest, or step all over someone's religious beliefs to climb a mountain. But that'd be asking humans not to be jerks, which is pretty tough for them to do. And so we'll continue to explore, and perhaps we should all hope that we learn something along the way that makes us not wreck things before we can understand them.