Kozushima, Tokyo

The ferry from 神津島港 docks on the western edge of the island, and the rhythm of the place announces itself quickly: fishing boats, a village bus making its loop, the smell of the sea. Kozushima sits well out in the Pacific as part of the Izu Islands, far enough from the mainland that the crossing itself — by ship from Tokyo, or by small aircraft out of Chōfu on 新中央航空 — marks a genuine threshold.

天上山 rises at the island's center, a dormant volcano whose summit offers trailheads through distinctive vegetation. Below, the coastline at 赤崎 is fractured rock and clear water, the kind of transparency that makes snorkeling feel less like recreation and more like inspection. The fishing grounds around 銭洲, far offshore to the southwest, draw serious anglers and divers for whom the surface world is almost beside the point. Obsidian — 黒曜石 — was quarried here in antiquity; the uninhabited island of 恩馳島, where the stone still surfaces, carries the weight of that long use quietly.

What the island produces tells its own story: 鰹節 tied to the bonito traditions observed at 物忌奈命神社, and 盛若, a local shōchū whose name most visitors encounter only after arrival. The village-run 温泉保養センター circulates into the bus route, unhurried. At night, the darkness here is the kind that earns formal recognition — the island holds a dark-sky designation — and the sky above 天上山 opens accordingly.