Mount Kusatsu-Shirane (or Mount Shirane) is an active stratovolcano in Kusatsu, Gunma Prefecture. This 2,160-meter tall volcano has had notable eruptions in 1983 and 2018. There are three crater lakes at the summit of Mount Kusatsu-Shirane. The largest is Yu-gama crater lake; with its turquoise blue waters and rafts of yellow sulfur, it makes for a striking and mysterious vista to all who visit. It is also the most acidic lake in Japan.
As of January 23, 2018, the summit of the volcano has been off-limits to the public. This closure includes the three crater lakes.
The volcano and its crater lakes, located just outside of Kusatsu Onsen Town, are a popular tourist destination, especially in autumn when the leaves are at their most vibrant. Hiking trails circle the crater lakes and make the hiking season, from mid-April to early November, a wonderful outdoor excursion. The most popular path is the from the Shirane Resthouse to Yu-gama. Thanks to the paved trail, the walk takes only ten minutes and is easy for people of all ages and skill.
A 30-minute bus ride from the Kusatsu Onsen town center Kusatsu Bus Terminal to Shirane Resthouse.