Mt. Chausu-dake is an active stratovolcano located Nasu, Tochigi Prefecture. It is one of 5 summits of Mt. Nasu and it is the main mountain. There are several fumaroles on the west side. The fumarole is called Mugen Jigoku.
Because it has a ropeway, the trekking to the top of Mt. Chausu is very easy. Therefore, it is very popular hiking spot in Kanto.