Aogashima

Aogashima is a volcano that happens to have a village on it. The outer rim rises straight from the sea, and inside the crater sits a second, smaller cone, Maruyama, with a walking path that loops it in about an hour. The best view of the whole arrangement is from Oyama Observation Park, around 400 meters up on the northern rim, or from Otonbu, the island's high point at 423 meters. Near Maruyama, steam the islanders call hingya vents from the ground; it heats the village-run Fureai Sauna and a geothermal pot where you can steam eggs and potatoes. Reaching the island is the hard part. From Hachijojima the Kuroshio Maru takes about three hours, sails only four or five days a week (never on Sundays or Thursdays), and because the harbor is exposed only 50 to 60 percent of those sailings actually go. The alternative, a 20-minute helicopter hop, has nine seats a day. There are no restaurants, and only a handful of guesthouses, so book a room with meals before you set off.