Sakurajima is the volcano you cannot stop looking at. From any waterfront window in Kagoshima it sits across the bay, a textbook cone with a smoke-plume that drifts east or west depending on the wind. It is one of the most active volcanoes in the world, registering minor eruptions on most days; the ash falls on the city often enough that locals carry small yellow bags for it.
The fifteen-minute ferry from Kagoshima port runs around the clock and takes cars. On the volcano side, the visitor centre, Yunohira lookout and lava-field walks at Arimura can be linked by the Sakurajima Island View bus, which loops the western half of the peninsula in about an hour. The Magma Onsen, an outdoor hot spring at the foot of the volcano, is the cleanest way to end a visit — the water is iron-rich and brown, and the volcano steams above you while you soak. Walking on the actual summit is forbidden; the closest you can get is the Yunohira observatory at 373 metres.