use Google Maps to explore two underground sights in Japan: the old Okubo-mabu mine and the Akiyoshi-do limestone cavern. Read the +Mashable article for more details.
And if you're interested in Google news in Japan, don't forget to follow +Google Japan!
And if you're interested in Google news in Japan, don't forget to follow +Google Japan!
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Google Japan has made spelunking from your desk a reality. Photo crews capture two Japanese caves and both are now online for you to explore.