(Snowman 2008 Organizing Committee, Hakusan City)
The Japanese archipelago extends a long way from north to south, and there's a great deal of regional variation in the climate. In Hokkaido and the Tohoku region in the north, it gets very cold and snows a lot during the winter. These areas are known as yukiguni, or "snow country."
A variety of indoor heating equipment has been developed in the snowy regions. Among them, the kotatsu is very popular even in areas where winter is not so severe. A traditional kotatsu consists of a wooden frame built over a heat source on the floor and covered with a futon (quilted blanket) so that people can warm their legs. Today, electric heaters built into the frame of the kotatsu have replaced charcoal as the heat source.
(The Japan Forum)
It is hard to resist the comfort of a kotatsu on cold days, but kids are full of energy even outside in the snow. Some popular ways of playing with snow are making yuki-daruma (snowmen), building kamakura (little snow huts) by hollowing out hard-packed mounds of snow, and yuki-gassen (snowball fights). Interestingly, Japanese snowmen are made of two balls of snow, one for the body and another for the head.
Winter sports, such as skiing and snowboarding, are popular as well. They're even part of the physical education curriculum at schools in snowy regions.