* The Paraguayan Gran Chaco is a largely inhospitable thorn forest where some of the Indian tribes have never had contact with the outside world.
* Great Atrato Swamp in the Darien jungle between Panama and Colombia is a deep forest area of insects and alligators, so difficult to negotiate that it’s mostly unexplored.
* The hill country of Burma, is said to be rich in treasures and lost cities but has been rarely explored since 1946 because of the closed border.
* The sheer difficulties posed by the high ice desert of Greenland means its largely unexplored. As are the tributaries of the Blue Nile in Ethiopia
* The Gangkhar Puensum has the distinction of being the highest un-climbed mountain on earth. The government of Bhutan has prohibited climbing the mountain due to religious beliefs.
* Vast areas of Siberia are largely either ice or mountain waiting to be fully explored.