Onuma-Koen
Nanae
Nature’s Masterpiece: An Introduction to Onuma-Koen
Hokkaido’s Gateway to Serenity
Located just north of Hakodate, Onuma Quasi-National Park (Onuma-Koen) serves as one of Hokkaido’s most accessible and breathtaking natural escapes. The park is centered around two main lakes—Onuma (Large Lake) and Konuma (Small Lake)—which were formed by the volcanic eruptions of the nearby Mount Komagatake. These lakes are dotted with over 100 small islands, many of which are connected by a charming network of walking paths and bridges that allow visitors to "walk on water" through the forest.
The park offers a refreshing change of pace from the urban energy of Hakodate. Visitors are greeted by a landscape that shifts dramatically with the seasons: vibrant greenery in summer, fiery maples in autumn, and a pristine white wonderland in winter. Whether you are looking for a vigorous hike or a quiet spot to sit with a coffee and watch the water, Onuma-Koen provides a scenic backdrop that feels like a living painting.
The Sculpted Landscape: A Brief History
Born of Fire and Time
The dramatic topography of Onuma-Koen is the direct result of the volatile history of Mount Komagatake. Centuries of volcanic activity, specifically a massive eruption in 1640, caused debris to dam the local river systems, creating the basins for Onuma and Konuma lakes. The "islands" that visitors admire today are actually the remains of the mountain’s peak that collapsed and settled into the water, creating a unique geological fingerprint found nowhere else in Japan.
Recognizing its extraordinary beauty and ecological importance, the area was designated as a Quasi-National Park in 1958. Long before it became a tourist destination, the region was inhabited by the indigenous Ainu people, who held the mountain in high spiritual regard. Today, the park is preserved not only for its recreation but as a testament to the raw power of Hokkaido’s volcanic heart.
Why Onuma-Koen is a Must-Visit
A Photographer’s Paradise
The primary draw for most visitors is the unparalleled view of Mount Komagatake. The mountain’s jagged, uneven twin peaks provide a striking contrast to the soft curves of the lakes below. On a calm day, the reflection of the volcano in the water is a bucket-list shot for photographers.
Endless Ways to Explore
Whether you prefer two wheels or two feet, Onuma is built for movement. A popular 14-kilometer cycling path circles Lake Onuma, offering various vantage points that most car-bound tourists miss. For those who prefer the water, sightseeing boats and rowboats offer a closer look at the lily pads and hidden inlets of the archipelago.
The Flavors of Hokkaido
No trip to Onuma is complete without tasting the local "Onuma Dango." These small, skewered rice dumplings represent the lakes themselves and have been sold at the station since the Meiji era. Tasting these treats while overlooking the water is a cultural experience that connects you to over a century of travelers.
Year-Round Accessibility
Unlike some Hokkaido parks that become difficult to access in winter, Onuma remains vibrant. When the lakes freeze over, they become a hub for pond smelting (fishing through holes in the ice) and snowmobiling. The park's proximity to the Shinkansen line makes it a seamless addition to any Hokkaido itinerary.
A Haven for Wildlife
For nature enthusiasts, the park is a thriving ecosystem. It is a sanctuary for various bird species, including majestic swans that migrate here in the colder months. Walking the quiet forested trails, you’re likely to hear the call of woodpeckers or see local foxes darting through the undergrowth, offering a true "wild" Hokkaido experience.
Planning Your Visit: What You Need to Know
Getting There and Around
The park is incredibly easy to reach, located right next to the JR Onuma-Koen Station. If you are coming from Hakodate, the Hokuto Limited Express takes only 20 minutes, while local trains take about 45 minutes. If you are arriving from Sapporo or Tokyo via the Shinkansen, the Shin-Hakodate-Hokuto station is just a short hop away, making Onuma an ideal "first stop" or "last look" at Hokkaido.
The Best Time to Visit
While the park is beautiful year-round, the autumn colors (typically late October) are legendary, as the maple trees turn a brilliant crimson against the blue water. If you visit in summer, be sure to rent a bike early in the morning to beat the midday heat. In winter, dress in heavy layers, as the winds coming off the mountain across the frozen lake can be quite piercing.