Lake Onneto

Onneto is a quiet and beautiful lake on the west side of Mt. Mekan. Onneto means “old and large lake” in the Ainu language, and it is also called Goshikinuma because the color of the lake changes depending on the weather and other factors.
From the wooden observation deck along Route 949, you can see Onneto up close.
The lake has an altitude of 623 m, a circumference of 2.5 km, and a maximum depth of 9.8 m.

  • Please refrain from entering non-powered boats (canoes, etc.) and swimming.


If you go about 1.5 km on the roadway from Meakan Onsen to Onneto, you will see the brown-colored swamp “Nishikinuma” in the forest on your left. Nishikinuma is a swamp with a circumference of about 200 m, and it has a brownish-brown color due to the accumulation of limonite.

Onneto Yunotaki Falls

Onneto Yunotaki Falls is approximately 1.4km,or twenty minutes on foot,from the forest road entrance at the parking lot near the Onneto Campground.Onneto Yunotaki Falls is home to microorganisms that produce manganese oxide.The scale of the manganese deposit found here is extremely uncommon,making it an important site for research on how manganese is formed in nature.In 2000,it was named a Natural Monument for its rarity.

Onneto Trail

There are four trail around Onneto.
You can enjoy different scenery on each course, such as a course that climbs to the observation point overlooking Mt. Meakan and Onneto (A), a course that walks along the lakeside (B), a course that walks through the forest (C), and a course that walks to Yuno Falls (D).

※There are three toilets in the neighborhood: ① a public toilet in front of the Meakan Onsen parking lot (all year round), ② a toilet at the Onneto National Camp (only from June ~ October), and ③ a UPI Onneto rest house (an outdoor shop open only from June ~ October).

A. 展望台コース(Observation Deck Course)
Distance:approx 2.3km(one-way) 

The observation deck course starts near the lakeside observation deck and takes you through a rich forest. After climbing for about 0.8 km, you’ll arrive at a rest area with a panoramic view of Onneto, Mt. Meakan, and Mt. Akan Fuji. This course is recommended for those who don’t have time to climb Mt. Meakan, but would like to enjoy the view from a slightly higher vantage point.

B. 東岸コース(East side lakeside course) 
Distance:approx 1.9km(one-way) 

This walking trail is on the eastern shore of Lake Onneto, and you can enjoy the scenery of Lake Onneto while walking through the moss-covered forest.
We also recommend the area where the brown waters of Nishikinuma flow into Lake Onneto, creating a beautiful contrast with the blue lake. You can also see the white flowers of Asian skunk cabbage in May.
*You can also walk around Lake Onneto by following the road on the western shore.

C. 雌阿寒温泉コース(Meakanonsen course)
Distance:approx 2.4km(one-way) 

This course connects Meakan Onsen (Nonaka Onsen) and Lake Onneto. Along the way, it joins up with Course B, which runs along the lakeside.
This course takes you through a beautiful forest filled with a variety of mushrooms to Lake Onneto.

D. 湯の滝コース(Onneto Yunotaki Falls course)
Distance:approx 1.4km(one-way) 

This is a walking course that takes you to Onneto Yunotaki Falls.
To get to the falls, you can walk along a wide, gentle forest path that continues from the parking lot in front of the Onneto National Campground.

Lake Onneto in winter

The lake usually freezes over between the end of November and early December when certain conditions are met. If you go before the lake is covered in snow, you can see spectacular views that are unique to this time of year, such as ice bubbles and Mt. Meakan reflected in the frozen lake surface.
*There are areas of frozen Onneto that are not frozen and areas where the ice is thin, so there is a risk of falling into the lake. Please take sufficient safety precautions when walking around. Please be especially careful on hot days.

During the winter, the road to Onneto (Route 949) is closed beyond Meakan Onsen, so you cannot go by car. You can only walk to Onneto from the Meakan Onsen Municipal Parking Lot (toilets available even in winter) via “course C” or Route 949. There is almost no mobile phone signal beyond Meakan Onsen, and it takes a long time for ambulances to arrive in the event of an emergency. Please prepare well before hiking, including snowshoes and checking the route in advance. If you have any concerns, we recommend using a guided tour provided by a private company.