Kuroshima Island
Evidence of volcanic ash
This circular island, about four kilometers off the shore of Fukue Island, had a population of one as of this writing. It is made up of basaltic lava and volcanic ash. The ash can be seen as soon as one disembarks at the harbor in a large open face displaying two distinct layers of ash: black below and dark brown above. A sea arch is visible across a small bay almost directly to the east. Sea arches are usually created by erosion from wave action, but it is possible this one is the remains of a lava tube. A number of houses still stand just beyond the harbor, a reminder of a very different time not that long ago when the island had a much larger population.