In the package – basically two sheets laid over the top of one of the concrete-encased fumaroles – were freshly-cooked sweet potatoes. Basically, the women were using volcanic outgassing as a kind of large steam-cooker. Picture a visitor in Yellowstone National Park hopping out of their RV and boiling hot dogs in Old Faithful. Only the people of Unagi make their permanent homes on top of this active volcano.
Armed with not a word of Japanese, but a big smile, I walked around the wall and signaled that I would like to take a photo. Soon all three of us were invited to try the potatoes. I had expected a possibly sulphurous, rotten-egg taste, yet they were perfect.
Whilst boiling food in hot geothermal waters has been documented in a number of places, I have never before heard of steam-cooking on a fumarole. Japan is a country full of surprises for the foreign visitor.