Ginzan Onsen, Yamagata
http://www.ginzanonsen.jp/index.htm
Small Onsen village. "Far, but it is worth a trip if you want to put yourself in real-old Japan life" ... by Kamei

Miyako-jima, Okinawa
Small Island in Okinawa. Not so famous yet for foreigner, so you can expact quiet and relax holiday.
You'll see the most beautiful sea in Japan.
Information (English)... http://www3.city.miyakojima.lg.jp/kankou-english/
Recommendable villa... http://www.neela.jp/Ginzan Onsen, Yamagata
http://www.ginzanonsen.jp/index.htm
Small Onsen village. "Far, but it is worth a trip if you want to put yourself in real-old Japan life" ... by Kamei