Ryusendo Cave is one of the Three Great Limestone Caves in Japan and a national natural monument. It is an extensive limestone cave in the mountains of Iwaizumi Town in Iwate Prefecture.
The portion of the cave which has been explored stretches over 3,500 meters since surveys began in 1920s. the entire cave is estimated to be over 5,000 meters into the mountainside.
It has some crystal clear blue lakes in the cave. The most impressive is the third lake, with a depth of 98 meters and beautiful emerald-green water.
700 meters of Ryusendo Cave is open to the public and made accessible via elevated walkways, bridges and stairs. Visitors can walk along the underground river that flows through the cave entrance, and explore several caverns and galleries on their way to the underground lake.
After visiting the lakes, the route leads up to a chamber that is just 35 meters below the surface of the mountain. Visitors can also see unique formations such as stalactites and stalagmites, as well as rare long-eared bats.
Take the bus from Morioka or Miyako. Both buses will pass through the Ryusendo Cave.
Try to be early, only 8 buses (4 for each) have that route.
The cave opens at 8:30 to 18:00 and until 17:30 from October to April.
No closing days.
Admission fee is 1000 Yen.