Lake Ashi Cruise

Three volcanic eruptions 3,000 years ago carved the caldera that holds Lake Ashi, a crescent of water 21 kilometers in circumference and 43 meters deep at its lowest point.

The modern sightseeing fleet launched in 1950, and by 1964 the first European-style replica vessel—a red-hulled paddlewheeler modeled on Mississippi riverboats—joined the line. Today's pirate ship fleet, introduced in 2007, draws from 17th-century French warship designs, complete with gilded figureheads and cannon ports.

Each leg takes 25 to 35 minutes, with vessels departing every 30 to 40 minutes during peak hours.

The flagship Royal II—launched in 2019—carries 580 passengers across four decks and features observation lounges with floor-to-ceiling windows and a bow promenade open to the elements. Her sister ship, Victory, replicates an 18th-century British man-of-war with mast rigging and a carved lion figurehead. Both vessels operate year-round, navigating waters that remain ice-free due to the caldera's geothermal vents. Morning light turns the lake steel-blue; by afternoon, thermal currents stir mist that can obscure Fuji entirely. The lake's pH sits at 7.8, and dissolved minerals from the volcanic basin give the water a faint sulfur scent near Ōwakudani's geothermal vents upstream.