When it comes to the first autumn leaves, it is the Taisetsuzan mount range in Hokkaido. The highest mountain, Mt.Asahidake to Mt.Kurodake in Hokkaido, is the best sight for autumn leaves. From here, the autumn leaves go extending everywhere all over the Hokkaido day by day. After autumn leaves, you can enjoy Onsen, hot spa in Sounkyo, Asahikawa. There are many hot spas and Ryokan. Staying for a couple of days, it is a good idea to climb a mountain all day long. You can go to the entrance of Mt.Kurodake by car and transfer a ropeway and a lift to the 7th stage where people start their ascent to the summit. Just 30minutes climbing. But, you have to prepare your equipments for climbing, especially shoes. This is really worth visiting in Autum, I swear.