Aso volcano is active and yet the huge caldera that formed 80,000 years ago is home to some 100,000 people, who live in the village of Aso and a dozen or so other villages in the north and whose livelihood depends on breeding and farming on the fertile slopes of Mt Aso. The Volcano Museum provides a good introduction before you set off to explore the volcano's five craters, an expedition that of course should be undertaken with due caution. To unwind afterwards, why not relax in the hot baths of Kurokawa Onsen?