Unexplored (adjective)

Not yet explored or investigated; not known or understood.

Origin:

From un- (not) + explored (to explore, to study or to examine).

Examples:

1. The jungle was unexplored and no one knew what secrets it held.
2. The depths of the ocean are still largely unexplored.
3. The scientist was excited to study the unexplored parts of the galaxy.
4. The cave system was unexplored, and the team of speleologists were the first to map it.
5. The uncharted territory was unexplored and the team of adventurers set out to discover what lies beyond.