truly 'unknown' tribes. And yes... very possible some headhunters and cannibals still exist there.

Probably the most famous of the un-contacted tribes are the Sentinlese, living on North Sentinel Island. They will still kill you if you try to come onto the island.

But back to New Guinea... they know a few of these tribes exist and yet know nothing about them at all.... a bit unlike the un-contacted tribes in the amazon whom we know quite a bit about even if seldom if ever contacted. And it's odd to me... because -

If you look at New Guinea on Google Earth there really aren't any places VERY far from civilization... but apparently it's extremely rugged country... thus unexplored.