Hokkaido Official Tourism Site HOKKAIDO LOVE!

Set deep within the Hidaka Mountains, the Saru River Headwaters Primeval Forest is a designated National Natural Monument. This vast, untouched wilderness serves as the cradle of one of Japan’s most pristine rivers, offering a rare glimpse into Hokkaido’s ancient natural landscape.

Located on the Hidaka side of Nissho Pass, this forest is a sanctuary where nature remains remarkably pristine. As part of Hidakasanmyaku-Erimo-Tokachi National Park, it provides an important habitat for diverse wildlife, including Ezo deer and Ezo grouse. Dense stands of Sakhalin spruce, Japanese oak, and Erman’s birch create a landscape that has endured for centuries, preserving the region’s rich ecological heritage.

The forest transforms beautifully with the changing seasons. Spring brings fresh green foliage, while summer blankets the landscape in lush, deep greenery. In autumn, the dark green of the conifers contrasts dramatically with the brilliant reds and golds of the deciduous trees, creating a breathtaking display of color.

Even from National Route 274, visitors can appreciate the vast expanse of this ancient woodland. The gentle whisper of the wind through the trees, the fresh scent of the forest, and the profound silence invite visitors to immerse themselves in the timeless beauty of the Hidaka Mountains.