Lake Shikotsu

Of all the big Hokkaido lakes, this is the one closest to New Chitose Airport, and on a calm day it is hard to believe the water is real. The color the locals call Shikotsu blue comes from the clarity: little silt runs in, the climate is cold, and the shallows by the onsen village look lit from below. The lake fills a caldera formed by eruptions that began some 30,000 to 40,000 years ago, and at about 360 m it is the second deepest lake in Japan after Tazawa. That depth is why it almost never freezes, even this far north. In winter the Chitose-Lake Shikotsu Ice Festival sprays lake water onto frames until it builds into towers and caves of blue ice, usually from late January to late February, lit in color in the evening. Shikotsuko Onsen on the east shore has five hot spring inns, and Marukoma Onsen sits further round the shore. To the south rises Mount Tarumae, an active volcano; check the Japan Meteorological Agency's volcano information before hiking it. The main car park charges cars 500 yen a day from April to November. With one bus route and few departures, a day trip without a car needs planning.