Ryusendo Cave

Ryusendo Cave is a limestone cavern in Iwaizumi that extends approximately 3.6 kilometers into the mountain. The system contains four underground lakes connected by pathways, bridges, and illuminated routes through the passages.

The cave formed over millions of years as underground water dissolved the surrounding limestone. Japanese authorities recognized its geological importance in 1934 and designated it as a Natural Monument.

The cave holds meaning as a place where visitors come to witness the power of underground water and geological time. People use the space to connect with natural forces that shaped the landscape over millennia.

Visitors can walk through about 700 meters of the cave system on secure, well-lit pathways. The routes are well-maintained and provide close views of several underground lakes.

The fourth underground lake reaches about 120 meters in depth and is among the deepest recorded subterranean bodies of water in Japan. This lake remains hidden from most visitors who only explore the accessible passages.

Location: Iwaizumi

Part of: Top 100 Geological Sites in Japan

Website: http://iwate-ryusendo.jp

GPS coordinates: 39.86053,141.79728

Latest update: December 17, 2025 07:47