Remember the pirate base in the caves? Go there, go south, and look for a path along the frozen water near the edge of the map. Follow that path to the end.
I do not remember a pirate base (unless that is the monsters that found rosemary)
In the frozen caverns you can find an old campsite. It's where you got the Peridotite Crucible for Sage. There's boxes and beds in the area.
