A day trip we took back in December 2015.
From Wikipedia:
Lake Ashi (芦ノ湖 Ashi-no-ko?), also referred to as Hakone Lake or Ashinoko Lake, is a scenic lake in theHakone area of Kanagawa Prefecture in Honshū, Japan. It is a crater lake that lies along the southwest wall of thecaldera of Mount Hakone, a complex volcano that last erupted in 1170 CE at Owakudani. The lake is known for its views of Mt. Fuji, its numerous hot springs, historical sites, and ryokan. The lake is located on the Tokaido road, the main link between Kyoto and Tokyo. 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.
The name means “lake of reeds” in Japanese: 芦 (ashi) is “reed”, and 湖 (ko) is “lake”. The abundance of nature makes it popular with hikers. There are many trails with different levels of challenge.
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