Spelunking
Spelunking was the act of exploring a cave.

Travis Mayweather had an interest in rock climbing and spelunking. His experience with these activities helped assist Tucker and Reed in rescuing Denobulan geologists from the caverns beneath . ()

Jason Vigo was spelunking in caves on Camor V when he was beamed on board the  in 2370. Vigo noticed he was aboard a Federation starship and asked Captain Jean-Luc Picard to beam him back into the cave. ()

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Recreation