is a 2160 meter active volcano

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

 in Kusatsu, Gunma

Kusatsu, Gunma

is a small town in Agatsuma District in Gunma Prefecture, Japan. Kusatsu is situated about 1,200 meters above sea level. The active volcano Kusatsu-Shirane and the inactive Mount Tengu and Mount Motoshirane are located west of Kusatsu.-Climate:Due to the altitude Kusatsu's annual average...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. It is called Kusatsu Shirane to differentiate it from the Mount Nikkō-Shirane

Mount Nikko-Shirane

is a shield volcano in the Nikkō National Park in central Honshū, the main island of Japan. It stands at 2,578m high, and is one of the 100 famous mountains in Japan.It should not be confused with Mount Kusatsu-Shirane elsewhere in Gunma Prefecture.- References :...

 on the other side of Gunma Prefecture

Gunma Prefecture

is a prefecture of Japan located in the northwest corner of the Kantō region on Honshu island. Its capital is Maebashi.- History :The remains of a Paleolithic man were found at Iwajuku, Gunma Prefecture, in the early 20th century and there is a public museum there.Japan was without horses until...

. The summit of Kusatsu-Shirane volcano, located immediately north of Asama volcano

Mount Asama

is an active complex volcano in central Honshū, the main island of Japan. The volcano is the most active on Honshū. The Japan Meteorological Agency classifies Mount Asama as rank A. It stands above sea level on the border of Gunma and Nagano prefectures...

, consists of a series of overlapping pyroclastic cones and three crater lake

Crater lake

A crater lake is a lake that forms in a volcanic crater or caldera, such as a maar; less commonly and with lower association to the term a lake may form in an impact crater caused by a meteorite. Sometimes lakes which form inside calderas are called caldera lakes, but often this distinction is not...

s. The largest of these is Yu-gama, an acidic turquoise-colored lake with rafts of yellow sulfur

Sulfur

Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...

floating on its surface.