57km of shoreline and up to 117m deep, Kussharo-ko is Japan’s largest caldera lake. Visitors enjoy getting into the kon’yoku onsen roten-buro (mixed open-air baths: you will need a bathing suit), camping, fishing and hiking around the pleasant shores. Summer and weekends are often bustling with holidaymakers, plan your trip during the weekdays.
Location 15km west of Mashu Onsen, 2.5km northwest of Kawayu Onsen
Lake Type Caldera Lake (Japan’s largest)
Surface Area 79.3 sq-km
Highlights Wakoto Peninsula, Kotan Onsen, Ike-no-yu, Suna-yu
和琴半島 / Wakoto Hanto / Kussharo
This little peninsula at the southern end of Kussharo-ko is the perfect place for spend an active day. You can hike a 2.5km-long pleasant circumference nature trail on the peninsula takes about an hour, passes by the volcanic hot springs Oyakotsu Jigoku (オヤコツ地獄).
02 OPEN-AIR BATH
和琴温泉 / Kussharo / 24hrs / FREE
At the base of the Wakoto Peninsula, there is a free mixed open-air bath (24hrs) with gender-segregated changing facilities and a campsite. A few hundred meters away from the open-air bath along the peninsula’s southern shore, you will find a one-room free bathhouse of Wakoto Kyodo Yokujo (和琴共同浴場) with mixed bathing only (it is very hot and a shared changing area: not recommended for women).
03 AINU CULTURE
Kussharo Kotan Ainu Folklore Museum
弟子屈町立屈斜路コタンアイヌ民族資料館 / 1-11 Kussharo-shigai / 9am-5pm late Apr-Oct / ¥420
Designed by Kushiro-born architect Mozuna Kiko, this unique museum is located in the small Ainu kotan (village) on the southeastern shores of Kussharo-ko. Exhibits included local Ainu household implements and crafts. You can wear traditional costumes. Don’t miss a 30-minute video for Ainu history and culture (ask for staff).
04 OPEN-AIR BATH
コタン温泉 / Kussharo-Kotan / 24hrs / Closed 8am-4pm Tue & Fri / FREE
A man-made rocky mixed open-air bath by the lake, this scenic onsen is about 150m north of the Kotan Ainu Folklore Museum. In winter you can see swans from a bathtub. There are changing rooms, bring a bathing suit. The bath is maintained on Tuesday and Friday (8am-4pm) by locals.
Near the open-air bath, there is also a small bathhouse (Noon-9pm, to 10pm Jul-Aug / Closed Wed / ¥300) of Kotan Kyodo Yokujo (コタン共同浴場) with gender-segregated facilities.
05 OPEN-AIR BATH
池の湯 / Kussharo-Ike-no-yu / 24hrs / FREE
Tucked away within the lakeside forest, Ike-no-yu is Kussharo’s largest mixed open-air bath like a lukewarm pool (the water temperature is around 38C).
The gateway is about 4km north of Kotan Onsen, look out for the small sign marked ‘Matsuya Ryokan (まつや旅館)’ on your left. The bath is 200m from the lakeside road. There are changing rooms, but night-time lighting is not available. The best bathing season is late spring to early autumn.
06 SANDY BATH & SCENIC VIEWPOINT
砂湯 / Biruwa / 24hrs / FREE
On the eastern shores of Kussharo-ko, you can find hot water in the sand here. Dig a hole for your own natural hot pool. Suna-yu is a popular spot especially group tourists and campers, you should wear a bating suit if you want to soak in hot water. There are no bathtubs and changing rooms.
On weekdays, Akan Bus runs two times a day from the Mashu Eigyosho (摩周営業所: 6.45am and 4pm) in Central Teshikaga to Wakoto Hanto (和琴半島: 35min). The return buses from Wakoto Hanto are at 7.20am and 4.35pm. Note: Mashu Eigyosho bus station is a 10-minute walk south of JR Mashu Station (on the JR Senmo Line) next to Teshikaga post office.
Otherwise, it is recommend you to explore the shores with your own wheels. Most attractions can be reached by the seasonal Kussharo Bus (屈斜路バス) for Teshikaga Eco-Passport (弟子屈えこパスポート) holders. More info about Teshikaga Eco Passport www.eco-passport.net.