It's probable... [ She muses with some consideration, glancing back with a thought: ] This does look like a place carved out of something that's already here so there's got to be caves.

[ Miyako glances back, to beyond the Lodestone and groans: ] But it's still a terrible idea to go wandering around in a cave system you don't know! What if you get lost? It'll be too dark!

[ Surely, they must have a pathway from people getting there in the first place - but she feels very underprepared for any kind of spelunking. Still, it's swim, spelunk, or starve. ]