Mount Meakan Onneto Trail was added to Your Favorites!
Akan-Mashū NP, Hokkaido
Claim this place to tell your story your way.
A branch off the Onneto route leads to Akan-Fuji, a separate volcanic cone formed roughly 1,000–2,500 years ago. It is a much younger neighbor to Mount Meakan’s older volcanic peaks.
The Onneto you glimpse from the trail was formed when Mount Meakan’s volcanic deposits blocked a river. Its blue-green hues are thought to blend clear blue water with yellow, mineral-rich lakebed mud; depth and sunlight shift the mix.
In the shady forest, look beneath rocks for hikarigoke, or “luminous moss.” It makes no light of its own: lens-shaped cells reflect faint ambient light, giving the moss an emerald glow.
Crowberry grows among the route’s alpine plants. Its nearly black berries are bitter fresh but are used for jam or juice; Ashoro’s local account also records Ainu uses of the juice for food, dye, and medicine.
The route’s summer meadows are home to 2 plants named for Meakan: Meakan-fusuma, first discovered on the mountain, carpets the ground with tiny white flowers; Meakan-kimbai is endemic to Hokkaido and listed as vulnerable.
Onneto’s chemistry shifts, too: researchers report its pH changing from about 5.2 (acidic) to 8.2 (weakly alkaline) over just a few years, without human intervention. Changes in stream inflows may help explain the swings.
The Ainu name Onneto has more than one interpretation: “old lake,” or “parent” or “large lake,” in contrast to nearby Ponto, meaning “child” or “small pond.” The trail begins beside Onneto.
The climb passes through distinct plant zones: mixed forest gives way to creeping pine around 1,000 meters, then to bare rock and gravel above about 1,100 meters. The scenery changes as dramatically as the footing.
