Chichijima has a network of marked trails through subtropical forest, old wartime roads, ridges, and viewpoints over Futami Bay. The walking is not alpine, but it is distinctive: pandanus, endemic plants, fruit bats at dusk, and sudden views over an island group that feels very far from the rest of Japan.
Some routes pass wartime remains, including tunnels and old military roads. Stay on marked paths, both for conservation and because unexploded ordnance remains a real issue on some islands in the archipelago.