Eating eggs boiled in volcanic water is tasty. Taking bath in volcanic hot springs reduces joint pains, so many people go for many days just to take bath in such hot-springs.
The result of a volcanic eruption over 3,000 years ago, Owakudani is a volcanic valley with active sulfur vents and hot springs. This area is one of the most famous tourist attractions in Hakone due to its volcanic activity and striking scenic views—you can even catch an amazing view of Mt. Fuji on a clear day. Due to volcanic gases, the area is sometimes closed. Sulfur and water vapor are spouted out at about 100°C, as a result the rocks have become clay, trees die, plants struggle to grow, and the mountain’s crust is visible for all to see. All of this together creates an image of hell that even prompted famed Japanese Buddhist monk, Kūkai, to offer a prayer to Bodhisattva at the sight. At sunset, the sunlight from Lake Ashi glitters off the waters to offers a beautiful sight one might not expect next to the nightmarish landscape.
AloJapan.com