boat passes through the rock tunnel washed out by the surf, oki islands, shimane, japan, unesco global geopark.

oki islands japan unesco global geopark rock formations sea japanese includes remote island scenery scenic geologic volcanic majestic cliffs coves caves coastline shimane breathtaking landscape rugged wild coast colors rust red ocher brown rocks breakthroughs view vegetation unique famous landscapes cliff layers marina environment steep define one tunnels boat passes tunnel washed surfrock surf geopark