Otaru is a port city about 30 min. by rapid train ride from Sapporo. Otaru is a tourist city and many at Sapporo make a weekend day trip to Otaru.

Hope I am not going off-topic, but about onsen town in the Tohoku area. Ginzan Onsen in Yamagata is very popular lately even among young people. Ryokans at Ginzan Onsen are usually booked solid these days. The reason for this popularity is that many believe Ginzan Onsen was used as a model for Studio Ghibli's 2001 movie Spirited Away. The director and the writer of the movie, Hayano Miyazaki, has not said Ginzan Onsen was used as a model for the movie but many believe and this popularity today. Ginzan Onsen is a traditional old fashion onsen town in a secluded area of Yamagata. Ginzan Onsen is not a resort setting by European or the U.S. standard in any stretch of the imagination. But there are enough daytime visitors who could not get a room at ryokans at Ginzan Onsen, Ginzan Onsen issues winter time advisory/warning for people visiting Ginzan Onsen as a day trip. I know, English is typical "Japanese English" but you get an idea.