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The cave systems are the last frontier of Earth's exploration. We don't actually know the full extent of the cave networks below us.
by dukeofdoom 5y ago
The cave systems are the last frontier of Earth's exploration. We don't actually know the full extent of the cave networks below us.
- BelenusMordred 5y agoDeep oceans surely fit the bill as well? We've mapped something like one-fifth of the sea floor.
- dukeofdoom 5y agoFor sure, but are there caves below the oceans?