Yuki Matsuri in Sapporo

I think it's a great idea. I usually go to the Alps for my winter holidays, but last year my friend took me to Sapporo and I liked it a thousand times better than the Alps. It's a snow festival that lasts from 5 to 11 February where you see an international snow sculpture competition, nightly concerts in the park and a bunch of other fun activities. If you do decide to go, try to get there about a week in advance to watch the artists make the sculptures or even participate in the creation process. And also book well in advance both your flight and a room because it's extremely crowded.