Mt. Hiyoriyama Observatory

Although Mt. Hiyoriyama Observatory’s name may be misunderstood as an observatory on Mt. Hiyoriyama, it is actually one that is dedicated to looking at the mountain. In general, "Hiyoriyama " refers to a place with a nice view that is ideal for weather analysis and these kinds of places exist all over Japan. The Hiyoriyama of Noboribetsu, however, was given its name when a ship going through the Pacific Ocean observed the amount and direction of Mt. Hiyoriyama’s smoke to determine the weather conditions. It is believed that the lava dome of Mt. Hiyoriyama was formed by volcanic activity that began about 15,000 years ago at the foot of the western side of the Kuttara volcano. In addition, the latest eruption was estimated to have occurred about 200 years ago in the crater row connecting Mt. Hiyoriyama, Oyunuma, and Jigokudani (Hell Valley), and it is still an active volcano that produces volcanic fumes. Oyunuma and Oku-no-Yu, which are seen below, are the traces left by the eruption of Hiyoriyama. Although it can not be seen from this observatory, Jigokudani was created from an eruption from Hiyoriyama volcano. Nearby, Hiyoriyama Native Wild Garden is located about 5 minutes by car from the observatory. There, you can see alpine plants such as Lysimachia vulgaris in July, willow herbs in August and Gentiana triflora in September.