Would you dare enter one of Japan’s deepest caves?
That question was on my mind as I stepped into Ryusendo, a limestone cave hidden in the mountains of Iwate. One moment, I was standing in the heavy, sticky summer air, listening to cicadas. The next moment, a sharp chill enveloped me, and I felt as though I had entered another world. The sweat on my skin made me feel cold as the temperature dropped. With each step deeper into the earth, I followed the sound of dripping water into the shadows.
The Great Blue Lakes
The cave opened up in stages: narrow stone tunnels led to vast rooms with damp, still air.
My eyes adjusted, and I saw the first of the underground lakes. Even with little light, the water glowed an eerie, deep blue. It was so clear it looked unreal, like glass in the dark. The deepest lake is about 120 meters down, but at that moment, facts didn’t matter. The silence and the feeling of standing before something ancient were what struck me. It felt less like a tourist spot and more like a secret the earth itself was whispering.
A Hidden Ecosystem
Then came the bats. Bats are rare in Japan, but five different species live in this cave. As I walked through a darker part of the tunnel, three of them swooped over my head. They were gone in a flash, but I still ducked as they passed. For a second, my heart jumped, not from fear, but from excitement. The cave wasn’t just frozen rock and water for visitors; it was alive.
The Legend of the Spring
There’s also a legend surrounding the spring water. It holds a belief that drinking it can prolong life by three years. Whether the legend is true or not, I don’t know, but the cool feeling of being refreshed from the summer heat and humidity felt like it added at least a few days for me.
Returning to the Sun
When I stepped back into the daylight, the summer warmth returned. It felt different, less heavy, almost comforting after the cave’s cold hug. I had gone into Japan’s hidden depths and returned with a memory few other travelers would seek out.
Practical Tips for Visiting Ryusendo Cave
- Location: Ryusendo Cave is in Iwaizumi Town, Iwate Prefecture, in the Tohoku region of northern Japan.
- Getting There: From Morioka (the prefectural capital), take the JR Yamada Line to Miyako, then transfer to a bus bound for Ryusendo (about 2.5–3 hours total). Alternatively, it’s about 90 minutes by car from Morioka.
- Visiting: The cave is open year-round. Plan for at least an hour to explore the main visitor areas.
- What to Expect: Temperatures inside stay cool (around 10°C / 50°F), even in midsummer, so bring a light jacket. The walkways can be damp, so good shoes are a must.
When you visit northern Japan and experience the underground national treasure of Ryusendo, please let me know what you think. I’d love to hear about your experience.