The bedrock of Hakone Volcano viewed from the bottom of Senjin Valley.
The surrounding area of Dogashima is located at the bottom of the steep valley eroded by the Hayakawa River, and from the bank it is possible to see the bedrock, which is the foundation of the Hakone Volcano. The stratum is approximately 4 million years old and was developed as a result of sedimentary volcanic ash and pumice.
The Dogashima Onsen has a long history and it is said to have been found by Muso Soseki (1275-1351), a monk during the Kamakura and Muromachi period who is famous for his political as well as cultural achievements.
The Bedrock of Hakone Volcano
Hakone Volcano is an active volcano that became active about 400,000 years ago. Its bedrock is stratum that was formed before Hakone Volcano was created. In the bedrock of Hakone Volcano is “Hayakawa Tuff Breccia” commonly seen in places such as here in Dogajima, National Highway 1, and the Hayakawa riverbed along with Sugumogawa Andesite that is distributed along the Sugumo River.
Fossils found at Hakone
It is thought that at the time when the Hayakawa tuff breccia was formed, explosive eruptions and eruptions gushing out lava occurred, and the volcanic ejecta from this was deposited on the seabed. Fossils such as shellfish yielded from this stratum are important indicators to know the environment at that time. Additionally, fossilized shark’s teeth were found in the same stratum at Hakoneyumoto.
Jakotsu-keikoku Valley (Snake Bone Valley)
The origin of the name “Jakotsu (snake bone), comes from the silicon in the hot springs accumulating and forming sinter deposits that appear like snake bones. There is the “Taiko no Ishiburo (Taiko Stone Bath)” where Toyotomi Hideyoshi was said to have taken his vassals in the midst of the Odawara attack in 1590 (Year Tensho 18).In the year Meiji 11 (1878) the Fujiya Hotel opened and developed into a place where many foreigners visited. The exotic atmosphere with old-fashioned shops and the nostalgic townscape is characteristic of this location.