An active volcano you can walk to the rim of
Mt. Meakan (1,499 m / 4,918 ft) is one of the most genuinely active volcanoes in the Hyakumeizan list. It sits in the southwest of Akan-Mashu National Park in eastern Hokkaido and is monitored 24/7 by the Japan Meteorological Agency. Small phreatic eruptions occurred as recently as 1998, 2006 and 2008, and the official volcanic alert level is updated daily. Even on a quiet day, the standard route walks you directly to the rim of a steaming crater complex with three vents — a sensory experience that few accessible mountains in the world can match.
The trail and what makes it special
From the Meakan Onsen trailhead at roughly 700 m, the climb to the summit is only about 800 m of vertical gain and takes around two and a half hours up, two down. The lower forest of Erman's birch and Sakhalin fir gives way at the eighth station to a barren landscape of red volcanic gravel. From the ridge above, you look into the working crater: a steaming central vent, a milky-blue Aonuma ('blue pond'), and a sulphur-stained Akanuma ('red pond'). The trail circles part of the outer rim to the summit proper. On a quiet day you can hear the hiss of fumaroles from the crater floor below.
Three routes, one logical loop
Three trails reach the summit: the Meakan Onsen route from the south (shortest), the Onneto route from the west (alongside a postcard-perfect crater lake), and a longer route from Akan-ko Lake on the east. Most climbers do Meakan Onsen up, Onneto down (or the reverse), with a five-to-six-hour total. The Onneto end is reached by a short walk along the lakeshore, where the view of Mt. Meakan reflected in the water in autumn is among the most photographed scenes in Hokkaido.
Access is by rental car: Kushiro Airport is about 90 minutes away, Memanbetsu Airport about two hours. There is no train within useful distance of the trailhead, and only limited bus service runs as far as Akanko Onsen. Plan to drive, or to stay overnight at Nonaka Onsen, a small hot-spring inn literally at the Meakan Onsen trailhead.
When to go, and the volcanic-gas question
The hiking season runs late May through late October — longer than most Hokkaido peaks because of the lower elevation and southerly exposure. Mid-September to mid-October is the best photographic window: the larches around Onneto turn gold, and the contrast with the red volcanic gravel of the upper mountain is striking. After mid-October expect snow on the trail; by November this becomes a winter climb.
Always check the JMA volcanic alert before climbing. Level 1 ('be aware that the volcano is active') is the everyday state and is fine for hiking. Level 2 or higher closes the upper trail. Even at level 1, the sulphur fumes from the active vents can be irritating to throat and eyes when the wind carries them across the rim — a damp bandana or lightweight buff is a small piece of kit that makes a real difference.
Brown bears live throughout this national park. Density on Mt. Meakan itself is lower than on Mt. Rausu, but encounters are not unknown. Carry a bear bell, especially on the forested lower section of the Onneto trail before dawn.
What to pack
The peak is low enough that altitude is not a concern, but exposure is. Pack as for a 2,000 m peak farther south: long-sleeve synthetic or merino base, fleece or synthetic mid, full waterproof shell, gloves, beanie, ankle-supporting boots, and at least two litres of water (no reliable on-trail source). Add the bear bell, the damp bandana for gas, and you are ready. There is no hut on the mountain itself, so this is a strict day climb.
After the climb
Below the summit, the Akan caldera holds two more notable peaks — Mt. Oakan ('male Akan', 1,370 m) and Mt. Akanfuji — and Akan-ko Lake itself, famous for the rare marimo moss balls that grow nowhere else in Japan at this scale. A two-day trip pairs Mt. Meakan in the morning with an afternoon at Akanko Onsen, where the same volcanic plumbing that drives the summit also feeds the town's bathhouses. For those continuing the Hyakumeizan, the natural next mountains are Mt. Daisetsu's Asahidake to the north, or the volcanoes of Shiretoko Peninsula to the northeast.
