Anime blogger Danny Choo recently checked out the lava caves of Mt. Fuji, including the Fugaku Fuketsu (wind cave), which is cold year round and was previously used as a natural refrigerator, and the Narusawa Ice Cave, which looks to be even colder.

The caves were created by lava, and there are about 80 caves surrounding Mt. Fuji. Only a few are open to the public for unguided tours. More pics in the link below.

Mt Fuji Caves [DannyChoo]

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