This nature park is dominated by Mt. Komaga-take, a dormant volcano about 1200 meters high which is the easiest recognisable feature of the landscape in this part of southern Hokkaido. The name Onuma refers to the large number of swamps, wetlands and lakes at the base of the volcano. There are two major lakes with many islands. Hot vents from beneath the mountain ensure good supplies for local onsens and also the Shikabe Geyser.
The combination of heavy rainfall and snow melt, along with the temperate climate, creates a paradise for birdlife and a wide range of vegetation – the area has more diversity than most of the other parks in Hokkaido, and only the smaller Matsumae area has more biological diversity.
Volcano: The last major eruption was in the year 2000 when ash covered nearby areas including Shikabe. At a height of about 1130 meters, this is not the largest volcano on the island but it is impressive. Even when on the top of Mount Hakodate, Komagatake dominates the horizon. It is possible to hike to the top during the summer months. Ask a local guide for details regarding safety considerations.
Snow Mobiles: During the winter months Onuma provides a good location for snow mobiles. It is usually easier to learn on flat open areas such as frozen lakes or snow covered pastures than in forested areas. Snow mobiles (and even ice ready Go Karts) can be rented from a shop near the park entrance.
Lakes: In 1929, Mount Komagatake erupted and by blocking a local river created a lake and a large marsh. These wetlands provide plenty of opportunities for boating, kayaking, fishing etc during the warmer months, and ice fishing and snow mobiles during the winter. The ice is not of uniform thickness due to warm vents eminating from the volcano, so ask for advice before setting out. The water is not particularly deep, these lakes are basically swamps, but are often covered with water lilies and teem with birds. You can also hike around the lakes via the walking trails, and there are bridges connecting some of the islands. The trails can be a bit crowded on weekends during the summer, as are the tour boats. Bikes can be rented also.
Onuma Craft Beer: This small microbrewery was established in 1998 and has acheived a bit of a following amongst serious beer drinkers. It doesn’t have the scale or quality of the Otaru Beer brewery but as Onuma has become more of a tourist destination the brewery has expanded its line up to include an improved India Pale Ale and a Grolsch style brew. The pub is near the park entrance and is not a bad place to end up at the end of the day.
How to Get There:
If you are driving, just use Route 5. If coming by train, please note that almost all express trains between Hakodate and Sapporo stop at Onuma Koen Station. Enjoying Onuma is an easy day trip from Hakodate, but if visiting from Sapporo or Otaru it would be best to spend the night.