If unexplored land was explored then it would no longer be unexplored land, and that is why it is impossible to explore unexplored land.
Unexplored is an adjective.
An unexplored area inhabited by one's enemy may be called hostile territory.
because they didn't not that there were some area that wre unexplored.
The only area that was still unexplored in 1828 was Patagonia
Approximately 80 of Earth's land remains unexplored.
A person who discovers a way to an unexplored area is a Pathfinder.
unexplored.
impossible, mysterious, unaccomplished
Mary's attic
On medieval maps, unexplored land was generally labeled, Terra Incognita, meaning unknown land.
Unexplored areas are called "terra incognita" or "uncharted territory." These terms are used to describe regions that have not been thoroughly discovered, studied, or mapped.