Sakurajima

An active volcano four kilometres across the bay from a city of 600,000 people, erupting several hundred times a year. Most of those are small, a puff of ash and a rumble, but the ash lands on Kagoshima whenever the wind is wrong, and the city is set up for it: yellow collection bags on street corners, ash forecasts in the weather report, and people who keep an umbrella in the car for reasons that have nothing to do with rain.

Until 1914 it was an island. The Taisho eruption that year poured out enough lava to close the strait on the eastern side and join it permanently to the Osumi peninsula, and you can drive across the join. At Kurokami, a shrine torii that stood three metres tall is buried up to its crossbeam in ash from that eruption; the village dug out the top and left the rest as a marker.

You cannot climb it. A two-kilometre exclusion zone surrounds the summit and the road stops well short. What you can do is circle it: the Yunohira observation point at 373 metres is the highest place open to visitors and looks straight into the craters, the Arimura lava observatory sits on the 1946 flow, and there are free foot baths and a lava trail at the visitor centre.

The volcanic soil grows two local oddities: daikon radishes that reach 30 kilograms and mikan oranges the size of a golf ball.

The ferry from Kagoshima takes fifteen minutes, costs a few hundred yen, and runs 24 hours a day. Concrete evacuation shelters stand along the island roads and are worth a second look; people live here, and they take the mountain seriously.