Yashimagahara Wetlands are located 1,540?1,925 meters above sea level and cover 3,000 hectares in the Kirigamine Highlands. The wetlands were designated a National Natural Monument in 1939. The wetlands are close to an obsidian mine at Wada Pass. Therefore, the surrounding areas of the wetlands contain prehistoric workshop sites. Some obsidian stone tools found from the wetlands are stored and exhibited at the Suwa City Museum.
Yashima Wetlands in Shigakirigamine Suwa City/Shimosuwa-machi Nagano