Yarilo
This mid-size planet was once abundant with life but has been a rocky lifeless planet for hundreds of years. It’s home to the Yarillian Cave System. The system has thousands of kilometers of mapped and explored caves, and potentially tens of thousands of kilometers still to explore.
Yarillian Cave Station
The Yarillian Cave Station is a designated Parks & Culture site on the planet Yarilo. It was established in the 1960’s. The station houses a permanent Parks and Culture team, which includes park rangers as well as revolving shifts of Planetary Archeology graduate students from universities around the galaxy and a fifty-person strong facility support staff. see Yarillian Cave Station
The Population
There are no permanent residents or native species. (though there is evidence that there could be some creatures living deep in the caves, but non e living have ever been seen or discovered).
Example: The best space hop of the year. A trip to the Yarillian Cave System.

Yarillian Cave System on Yarilo