Guide
Nozori-ko Lake is a serene dam lake located in Nakajo Town, Gunma Prefecture, within the scenic Josui-Kogen National Park. Surrounded by dense primeval forests, the lake offers a breathtaking landscape that feels like a natural, untouched wilderness. The lake was formed by the Nozori Dam, and its crest sits at an altitude of 1,517 meters—historically one of the highest dam crests in Japan. The area is a haven for nature lovers, featuring hiking trails and zones where rare alpine plants grow wild.
The lake was created by the Nozori Dam, a rockfill dam built across the Nakatsu River, a tributary of the Shinano River. Currently, the dam serves as a power generation site for TEPCO Renewable Power. The dam's crest is paved with asphalt, allowing it to function as a roadway that connects the two sides of the lake. It is worth noting that certain sections of National Route 405 near the dam are no longer open to through traffic, a measure taken to preserve the delicate natural environment.
The primary appeal of Nozori-ko Lake lies in its pristine waterfront environment and natural scenery. The lake is a popular spot for fishing, with trout and char released into the waters; visitors can enjoy fishing by purchasing a fishing permit locally. The seasonal changes in flora are also a major draw. In the summer, the area is adorned with beautiful alpine plants such as the Nozori-kisuge (a local variety of Daylily) and various species of Rhododendron. From the top of the dam, you can enjoy a panoramic view of the surrounding mountains and the shimmering lake.
When planning your trip, please pay close attention to the bus schedule. The local bus service only operates from May 1st to October 20th each year. This period coincides with the blooming of alpine flowers and the relatively cooler summer months. Please be aware that even in summer, the water temperature remains quite low, making the lake unsuitable for swimming. If you plan to hike or trek, it is essential to check the local weather and temperature forecasts, as conditions can change rapidly at high altitudes.
Visitors can immerse themselves in nature through hiking and fishing along the lakeshore. For fishing enthusiasts, the lake is home to rainbow trout and char (Iwana), though a fishing permit is required to participate. The area also serves as a gateway for hikers aiming to climb nearby peaks, such as Mt. Shirasuna. Activities are centered around low-impact, nature-focused exploration.
As part of the Josui-Kogen National Park, the area is surrounded by national forests, including the Nozori Natural Recreation Forest. Nearby famous hot spring destinations like Kusatsu Onsen and various sightseeing spots in Nakajo Town are also within reach. Note that certain sections of National Route 405 near the dam transition into rugged mountain paths, so please exercise caution if traveling by vehicle.
Cash is generally required for purchasing fishing permits or using the local bus services.
English language support and signage are limited in the surrounding areas. We recommend preparing in advance.
Please check the bus operating schedules in advance to ensure your visit aligns with the service dates.
Since the lake is located at a high altitude (approx. 1,500m), please dress according to the season. Even in summer, temperatures can drop significantly, so bringing layers for temperature regulation is highly recommended.
Photography of the scenery is permitted, but please respect the rules of nature conservation and do not disturb the environment.
While the dam crest is paved, many of the surrounding hiking trails and mountain paths are unpaved, featuring uneven terrain, steps, and steep slopes. Sturdy walking shoes are recommended.
Swimming in the lake is strictly prohibited. To protect the beautiful natural environment, please ensure you carry all your trash back with you.