Oze National Park
Japan's largest highland marshland (approx. 1,400m elevation) — a UNESCO Ramsar wetland of ancient peat bogs, alpine ponds, and rare mizubasho (skunk cabbage) lilies that bloom in May when snow still covers the mountain ridges around the plateau. Boardwalk trails cross the protected wetland habitat of Oze National Park (approx. 372 km²).
Full day
Conservation fee ¥500
Open mid-May to late October (varies by snowmelt); entry gates: dawn to dusk
Late May–early June (mizubasho), August (alpine hiking)
Bus from Numata Station to Oshimizu Trailhead (90 min)
Location
Why Visit
- 1
Mizubasho (skunk cabbage) blooms in May against snow-covered peaks — Japan's most dramatic flower hike
- 2
UNESCO Ramsar Wetland — a peat bog ecosystem formed over 10,000 years of volcanic activity
- 3
280 square kilometres of protected boardwalk trails reachable from three mountain passes
Local Tips
The largest high-altitude wetland in Japan — 2,000+ hectares of marsh, ponds, and alpine meadows at 1,400m. The mizubasho (skunk cabbage) blooms late May to early June, creating a white carpet across the wetland floor. The 8km main boardwalk circuit takes 3–4 hours. Book accommodation in the single mountain hut well in advance for an overnight wildflower experience.
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