Omijima Island — Untouched Coastal Wilderness

Omijima Island (青海島) is a rugged, uninhabited coastal wilderness where volcanic rock formations, sea caves, and towering cliffs create some of the San-in Coast's most dramatic scenery. Connected to the mainland by a short bridge, the island's 40km perimeter features geological formations nicknamed 'Marine Alps' — jagged pinnacles, natural arches, and wave-cut caves sculpted over millennia by the rough Sea of Japan. The official sightseeing boat (40-min circuit) navigates sea caves like 'Gate of Hell' and 'Elephant Rock,' approaching cliff faces where seabirds nest.

The island is part of Kita-Nagato Kaigan Quasi-National Park and remains largely undeveloped — a coastal hiking trail (4km, 90 minutes) traverses the eastern shore, passing viewpoints, small shrines, and fishing villages of 10–20 houses. The island's protected status prevents industrial development, preserving a wild coastline that feels centuries removed from modernity. Sunset views from Omijima Observatory show the sun descending into the Sea of Japan, painting volcanic rock formations in amber and crimson light.