Mar. 3, 2010 -- The last thing we would have expected to learn about food in Japan is an unusual way of cooking sweet potatoes. But the inhabitants of the tiny village on the shore of lake Unagi are not only effectively living in a volcano, but also put the volcanic gases rising to the surface in their back gardens to good use: they use them to steam-cook vegetables.

Very few foreigners venture to the volcanically active Satsuma Peninsula at the southern tip of Japan (pictured above is Mt. Kaimon). Had the weather been more suitable for viewing the spectacular eruptions of nearby Sakurajima volcano, which was the main focus for our small group of volcano photographers this past January, we would never have discovered the strange treasures of the Unagi crater.

The bottom of Satsuma lies in the massive volcanic Ata Caldera which was formed by the eruption of one of a whole series of supervolcanoes in southern Japan about 100,000 years ago. Smaller eruptions have occurred in more recent times, one of which forming the Unagi explosion crater about 5000 years ago.