The park is the oldest designated national park in Japan to incorporate a wetland landscape.
Ozegahara is the largest high-altitude wetland in Japan, situated at an elevation of approximately 1,400 to 1,700 meters.
The skunk cabbage (mizubasho) blooms in late spring and is considered an iconic symbol of the park.
The boardwalks were constructed specifically to prevent the erosion and degradation of the marsh's fragile peat layers.
Ozenuma Lake was created approximately 10,000 years ago when the eruption of Mount Hiuchigatake dammed the river.
There are no roads for private vehicles within the park interior, necessitating significant hiking to reach the core wetlands.
Oze National Park is a high-altitude plateau spanning Gunma, Fukushima, Niigata, and Tochigi prefectures, centered on the Ozegahara Marshland. The landscape is defined by vast volcanic wetlands featuring rare alpine flora, including skunk cabbage and daylilies. Over 60 kilometers of raised wooden boardwalks protect the delicate ecosystem from trampling. Visitors encounter the Ozenuma Lake, an alpine lake formed by lava flows from the surrounding mountains. The park serves as a critical habitat for diverse mountain wildlife, including Asiatic black bears and various migratory birds. It remains a strictly protected area under Japanese national park regulations to preserve its unique bog ecology.
The boardwalk section overlooking Ozegahara Marshland with Mount Hiuchigatake in the background.
Check the official park website for trail closures due to heavy snow, which can persist into early summer.
Pack out all trash, as there are no public waste disposal facilities within the park boundaries.
Bring specialized hiking gear, as weather conditions change rapidly at high altitudes regardless of the season.
Attempting a full traverse in a single day without prior fitness preparation or attempting to visit outside the summer operating season without snow-trekking equipment.
The park is generally closed to the public during the winter season due to heavy snowfall; access is typically limited to late spring through late autumn.
Stay strictly on the wooden boardwalks at all times; do not step into the marshland. Carry all waste off the mountain.
