
Panduan
Yashima Wetlands (Yashima-gahara Wetlands) is one of Japan's most iconic high-altitude wetlands, situated in the northwestern part of the Kirigamine Highlands in Nagano Prefecture at an altitude of 1,630m. Spanning an area of 43.2 hectares, its history is estimated to be as old as 12,000 years. Designated as a National Natural Monument in 1939, it holds immense academic and cultural value. The vast landscape, characterized by diverse plant life centered around sphagnum moss, creates a harmonious view with the surrounding mountains and blue skies, offering visitors a deeply moving experience.
This wetland has been shaped by the natural processes of the ancient world. The peat layer reaches a thickness of 8.05 meters, with organic matter accumulated over millennia supporting a rich ecosystem. Historically, the area has maintained a highly diverse flora, including 18 different species of sphagnum moss. The surrounding region has a long history of living in harmony with nature, and today, the wetlands are protected by hikers and nature enthusiasts as a vital part of the Kirigamine Highlands' landscape.

The greatest charm of Yashima Wetlands is the vibrant display of seasonal colors. In June, the area is blanketed in the bright colors of the Rengetsutsuji (Japanese Andromeda), and in July, the Nikko Kisuge (Daylilies) bloom in abundance. Visitors can also experience the "sounds of nature," such as the calls of the Schlegel's Green Tree Frog, which has been selected as one of the "100 Soundscapes of Japan" by the Ministry of the Environment. The perimeter walking course (approx. 3.8km) is well-maintained with gentle undulations, offering a panoramic view of the surrounding mountains.
The expression of the wetlands changes dramatically depending on the season:

Various activities allow you to connect closely with nature. A hike along the well-maintained perimeter course (approx. 1 hour 7 minutes) is relatively easy even for beginners. For more advanced enthusiasts, trekking in the surrounding mountains is also possible. Immersing your senses in the sounds of nature and the scent of plants provides a special way to escape daily life.
The area around the wetlands offers several facilities to enhance your visit. Along the