Hot spring inn with a cave (Mie,Japan)

I found a hot spring inn with a cave in Mie Prefecture, Japan, so I went there!
The cave dates back to the 1600s (Edo period).
It was used to collect polishing sand for abrasives, and during the war it was used as a propeller factory for fighter planes, and now it is used as a hot spring inn.

#Japan #JapanTrip #JapanTravel