Lake Ashi, also referred to as Hakone Lake or Ashinoko Lake, is a scenic lake in the Hakone area of Kanagawa Prefecture in Honshū, Japan. It is a crater lake that lies along the southwest wall of the caldera of Mount Hakone, a complex volcano that last erupted in 1170 CE at Owakudani. The lake is known for its views of Mt. Fuji and its numerous hot springs. A number of pleasure boats and ferries traverse the lake, providing scenic views for tourists and passengers. Several of the boats are inspired by the design of sailing warships.
Most visitors to Lake Ashi stay in the nearby resorts or visit some of the local attractions, including taking the aerial tram Hakone Ropeway to The Great Boiling Valley. From Togendai on Lake Ashi, the Hakone Ropeway aerial tram connects to Sounzan, the upper terminus of the Hakone Tozan Cable Car funicular railway. This in turn connects to the Hakone Tozan Line mountain railway for the descent to Odawara and a connection to Tokyo by the Tōkaidō Shinkansen.