Inazumi Underwater Limestone Cave
Open by month
Open in January. No seasonal closure recorded. New Year (Dec 29 – Jan 3): open.
Open in February. No seasonal closure recorded.
Open in March. No seasonal closure recorded.
Open in April. No seasonal closure recorded.
Open in May — at its best. Fireflies on the nearby Hakusan River (late May to mid-June).
Open in June — at its best. Fireflies on the nearby Hakusan River (late May to mid-June).
Open in July. No seasonal closure recorded.
Open in August. No seasonal closure recorded.
Open in September. No seasonal closure recorded.
Open in October. No seasonal closure recorded.
Open in November. No seasonal closure recorded.
Open in December. No seasonal closure recorded. New Year (Dec 29 – Jan 3): open.
Checked against the official site on 2026-10-19.
A limestone cave formed some 300 million years ago and flooded by a huge eruption of Aso, so its stalactites now sit under clear water. Cave diving is also offered.
Nearby
- Chinda Falls ≈ 30 min by car
- Harajiri Falls ≈ 30 min by car
- Oka Castle Ruins ≈ 40 min by car
- Hakusui Dam ≈ 50 min by car
- Nagayu Onsen ≈ 1 h by car
Travel times are rough estimates by car.
- Best time
- May, June — Fireflies on the nearby Hakusan River (late May to mid-June)
- Getting there
- About 20 min by taxi from JR Mie-machi Station
Easier with a tour or car - Fee
- Adults ¥1,500; junior/senior high ¥1,200; age 4 to elementary ¥900 (includes the other on-site facilities)
- Good to know
- 9:00-17:00 (longer in summer), open every day
- Time needed
- 1 h 30 min
Checked against the official Japanese website on 2026-10-19. Report outdated info