Ryusendo Cave

Overview

Ryusendo Cave is a limestone cave located in Iwizumi Town, Iwate Prefecture, and is considered one of Japan's three great limestone caves, alongside Akiyoshidai Quasi-National Park and Ryūgadō Cave. With a total length exceeding 1,200 meters and a vertical drop of 249 meters, it's renowned for its numerous underground lakes. Exploration was temporarily halted due to a diving accident involving a cave explorer; the actual length is estimated to be over 2.5 kilometers. The cave's interior is a breathtaking spectacle of stalactites and stalagmites of various sizes, creating a mystical atmosphere. The crystal-clear underground lakes, especially, are strikingly beautiful, often referred to as "Dragon Blue." The water boasts exceptional clarity and was selected as one of Japan's 100 Best Waters in 1985 (as "Ryusendo Underground Lake Water"). Ryusendo Cave is home to five bat species: Kikugasira-koumori, Kokikugasira-koumori, Momojiro-koumori, Usagi-koumori, and Tengu-koumori. These bats, along with the cave itself, were designated a National Natural Monument on December 14, 1938, under the name "Iwizumi Yūkutsu and Bats". Designated a National Natural Monument, Ryusendo Cave is a precious natural heritage site under protection. The nearby Japan Speleological Society Institute serves as a center for cave research. Ryusendo Cave is a truly remarkable tourist spot where you can experience the wonders of nature.