Lake Akan, or Akanko (阿寒湖) in Japanese, is one of the clearest and most transparent lakes in Japan. You can have a clear view of its water up to 3 to 4 meters deep. It is located in Eastern Hokkaido (北海道) in the region of Kushiro (釧路), and is situated between two volcanoes, namely Oakan (雄阿寒) and Meakan (雌阿寒), which refer to “male” and “female” mountains, respectively. Take note, however, that Meakan is still active so prior preparation is needed if you are planning to go on a hike.
There are some interesting things about Lake Akan that you must know – some unique natural phenomena take place only at this lake which might leave you in wonder. The lake is part of one of the most sensitive wetlands in Japan that is now conserved as a Ramsar Site. Lake Akan and its surroundings are also given a national park status due to its unique vegetation and rich scenery.
How was the lake formed and why is it an interesting place to visit?
Some thousands of years ago, the volcanic eruptions of Oakan and Meakan created a crater lake which is now known as Lake Akan. It is the birthplace of the Akan River which flows nearly 100 kilometers into the Pacific, creating a huge basin of approximately 718 square kilometers.
The entire region surrounding the lake is one of the pristine areas in Japan, and probably in the whole world. A nearby cousin lake of Akan, Lake Mashu (摩周湖), could be the clearest lake in Japan with a transparency level reaching 40 meters.
Due to the volcanic activity under Meakan, there are a number of hot springs emerging around Lake Akan. The place also offers some unforgettable beautiful views. The unique conditions make the lake give rise to some interesting phenomena, three of which are below.
Marimo is a group of algae species that grows as colonies of large-sized balls (usually up to 15 centimeters in diameter) under low light conditions and cold weather at the bottom of lakes in countries like Iceland, Estonia, and Japan. These algae are endangered with only a few places in the world remaining to witness them, the main one being Lake Akan where they grow up to 30 centimeters.
The government of Japan is doing its best to preserve these marimo balls by educating the people through toys and by conducting fairs with the support of locals who are Ainu. There is also a Marimo Observation Hall you can visit by boat on one of Lake Akan’s islands. In order to pass information about marimo to younger generations, the government declared marimo as a national treasure that must be conserved.
Kokanee salmon is one of the rarest freshwater salmon that is endemic to Lake Akan and nearby lakes. Unlike the rest of the salmon groups living in the Northern Pacific Ocean which migrate from rivers or lakes to oceans, the Kokanees spend their entire lives in Lake Akan. Conservation efforts are also under place to protect this unique salmon group.
Bokke are the hot pools of mud that are found in the swamp near Lake Akan in the forest trail. These pools are created due to the volcanic activity of the mountains in the region. Although not dangerous, proper precaution should be taken while dealing with the mud as they contain large amounts of sulphur. Bokke is another interesting phenomenon that happens near Lake Akan which you should not miss.
You can get more information about these phenomena happening in and around Lake Akan at its tourist center located in the small resort town of Akankohan (阿寒湖畔), namely Akan Kohan Eco Museum Center (阿寒湖畔エコミュージアムセンター). You can also find Ainu handicrafts and other things related to the indigenous group at the Akan Ainu Kotan (阿寒湖アイヌコタン).
You can reach Lake Akan from Kushiro either by bus or car which would take around one and a half hour. It is better to rent a car to explore the Akan National Park (阿寒国立公園) region as buses can be less frequent, especially in winter where the lake is completely frozen.