Guide
Yashimagahara Highland Marsh is a high-altitude marshland located at an altitude of approximately 1,630m on the Kirigamine Plateau in Nagano Prefecture. Designated as a National Natural Monument, it preserves a unique and delicate ecosystem. The area offers expansive views of the Kirigamine highlands, where visitors can witness the changing faces of nature through diverse seasonal plant life.
This region is a strictly protected area dedicated to preserving the natural environment. The high-altitude marsh ecosystem has been maintained over many years, serving as a vital habitat for rare flora and fauna. Local facilities, such as the Yashima Visitor Center (Asami Hall), play an important role in educating the public about and preserving this precious natural heritage.
The marsh features well-maintained wooden boardwalks, allowing visitors to navigate the terrain safely while observing the surrounding landscape. The primary attraction is the seasonal transformation of the vegetation. In June, the area is covered in Rengetsu Tsutsuji (Japanese Andromeda), and by July, the vibrant Nikko Kisage (Daylilies) bloom across the landscape. There are also various routes leading toward nearby peaks such as Mt. Kuruma and Mt. Kirigadake.
The landscape changes beautifully with the seasons. The visitor center is generally open from late April to early November. The peak viewing months are June and July, when the Rengetsu Tsutsuji and Nikko Kisage are in full bloom. Please be aware that summer often brings sudden thunderstorms, and the area is prone to heavy fog, which can rapidly change visibility. Always check the weather forecast before heading out.
The area serves as a base for various hiking and trekking activities. Popular routes include a gentle loop around the marsh (approx. 90 minutes) or a more challenging trek toward the Mt. Kuruma area (approx. 150–180 minutes). While the boardwalks make for pleasant strolls, those planning to hike the surrounding mountains should be cautious, as paths can become slippery after rain.
Nearby facilities include the Yashima Visitor Center and the Kuruma Visitor Center. Along the Venus Line, you will find various drive-in stations and local farm stands. Other nearby points of interest include Izumiko and the Hoshigatata Ruins.
