As others point out, there are sure to be many inhospitable places where no human has set foot – even if someone’s come within a kilometer of most of them.
Then there’s an entire island where some people do set foot every day – we can see them – but they don’t share with anyone else in the world.
It’s North Sentinel Island.
The people don’t want you. If you come near in a helicopter, they point arrows at you until you fly away.
They’re missing out on GPS, Wifi and ’60s rock music, but they might have the right idea. The last time that someone visited, 1879, they stole an elderly couple and some children – most of whom quickly died from disease.
They are aware of outsiders. They now have metal tools, after scavenging from shipwrecks.
The Indian government, acknowledging that contact with tribes on other Andaman Islands has only brought disease and dependency, has adopted a form of Star Trek’s prime directive. Orders are to leave the Sentinelese alone until they come to us or, for example, develop their own interstellar travel.
Edit: The Sentinelese still don’t welcome strangers, but Jon Hjalmar let me know that there were two friendly encounters with the Sentinelese in 1991. A team of anthropologists floated coconuts to them as “getting to know you” presents, and visited with them on one of their beaches.
Sadly, a young man tried to visit in 2018 and was killed.