# Lake Kussharo

> Japan's largest caldera lake, about 80 square kilometres, in Akan-Mashu National Park. At Sunayu hot water seeps up through the sand so you can scoop out your own bath, whooper swans winter on the unfrozen shallows, and the Wakoto Peninsula has a 2.5 km loop past steaming vents.

- Prefecture: Hokkaido
- Type: Attraction
- Address: Teshikaga, Hokkaido, Japan
- Hours note: The lake has no gate. The Sunayu sand beach is free and open 24 hours with no closing day.
- Official site: https://www.masyuko.or.jp/enjoy/kussharoko/

At Sunayu, on the east shore, the sand is warm underfoot and a few minutes with a spade turns up a pool of hot water, as large as you have patience for. The spring is sodium bicarbonate, it costs nothing, and it never closes. The same heat keeps the shallows here open in deep winter, when the rest of Lake Kussharo freezes over and temperatures drop below minus 20C. That is when whooper swans from Siberia crowd the beach, and on cold nights the ice cracks and rises into pressure ridges, omiwatari, up to about 2 m high. The lake itself is the biggest caldera lake in Japan, 79.7 square kilometres with a 57 km shore and Nakajima, a 5.7 square kilometre island, in the middle. On the south shore the gourd-shaped Wakoto Peninsula has a 2.5 km loop trail through old trees to the Oyakotsu Jigoku vents at its tip, two campsites and a free open-air bath. Do not expect fish or a lively waterfront: the water is acidic and private motorboats have been banned since 2021. Without a car you will struggle, as the lakeshore is spread out.

## FAQ

### Does it cost anything to bathe at Sunayu?

No. Sunayu is free and open 24 hours with no closing day. Dig a hollow in the sand at the water's edge and hot spring water fills it; the Sunayu rest house next to the beach has food and souvenirs.

### When can I see swans at Lake Kussharo?

In winter, when the lake freezes from around December and stays frozen until about March. Whooper swans from Siberia gather at Sunayu because the hot spring keeps the water there from freezing.

### How long is the walk around the Wakoto Peninsula?

The loop is about 2.5 km and passes large old trees on the way to the Oyakotsu Jigoku steam vents at the tip. The peninsula also has two campsites and a free open-air bath.

### Can I get to Lake Kussharo without a car?

It is hard. The JR Senmo Line stops at Kawayu Onsen and Mashu stations, but neither is on the lakeshore and the only listed sightseeing bus runs in winter. Rental cars are available in Teshikaga.

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Source: Lake Kussharo — Japan Voyage