TThe Izu Peninsula Geopark is designated as a UNESCO Global Geopark in April 2018. In Nishiizu, there are large, widely distributed strata from the submarine volcanic era, and you can observe these cross sections on the cliffs throughout the coastal areas. There are also many other wonderful natural landscapes that you can find here in Nishiizu!
One characteristic landscape you can observe in Dogashima is the layer of beautifully folded white volcanic ash on the coastal cliffs. Another interesting landscape is known as the Tensodo (sky cave), formed from erosion by the waves. Be sure to come admire the sky cave, either from the tour boat or from the boardwalk! Daily Geo-guided tours are also held in the area.
The name Sanshirojima means "Three or Four Boys Island" in English. The island received its name because you can see 3 islands from some angles, and 4 islands from other angles. From spring to early autumn each year, the Tombolo landbridge appears during low tide, allowing you to walk to Sanshirojima Island by foot.
Koganezaki means "golden cliff" in English, referring to the golden color of the rocks during sunset. The rocks are golden due to hydrothermal alteration, a phenomenon unique to geothermal areas formed by volcanoes. At the resting stop inside Koganezaki Park, there is a display introducing surrounding geosites, and from the observation deck, you can see Mt. Fuji and the mountains of Nishiamagi.
On the Futo coast, you can see a group of dikes, indicating past magma paths which supplied magma to former submarine volcanoes. Each of the vertically shaped rocks on the coast is a former magma path.
For more information about the Izu Peninsula geopark, please refer to the following site. Other than geosites in Nishiizu, locations in neighboring towns are also introduced. You can also check the information about facilities such as access information, parking lots and restrooms.