Ryusendo Cave is one of Japan’s three Great Limestone Caves, located in Iwaizumi, Iwate Prefecture, Japan. It is estimated that the caverns extend nearly 5000 meters into the mountainside, about 3500 meters of which have been explored to date since surveys began in the 1920s. You can easily see deep into the underground lakes, the deepest of which is 98 meters! There have a clear blue color that has been called Dragon Blue and boast a clarity that is one of the most prominent in the world. You can also see unique formations such as stalactites and stalagmites, as well as rare long-eared bats.
140 minutes by bus from JR Morioka Station (Tohoku Ryusendo direct flights)