Muroiwa-dong

During the era when the Izu Peninsula was an undersea volcano, volcanic ash deposited on the seabed transformed over long ages into tuff, a stone highly valued as a building material known as “Izu Stone.” Muroiwa Cave is the site of a quarry where Izu Stone was mined until the early Showa period. Developed for tourism, it opened in 1982. Visitors can observe the rock layers and quarry marks within the tunnel-like quarry while experiencing a bit of thrill. There is also a cave inhabited by bats. The cave spans approximately 2,000 square meters, with a walking path around the interior measuring roughly 180 meters. Handrails, lighting, and directional signs are provided at key points along the path, ensuring a safe visit. From the observation deck at the rear, visitors can enjoy views of the sea, the mountains toward Nishina, and on clear days, Mount Fuji. It is one of the geosites in Matsuzaki Town within the Izu Peninsula Geopark. Admission is free. Translated with DeepL.com (free version)