I recommend visiting - Tsumago, Japan
My favorite destination was really hard to choose but I had to go for Tsumago. It really set the scene as to how Japan was in the Edo period and it is a great historical experience walking through Tsumago postal town. Close by they also have the 'Momosuke' bridge which I absolutely love and its well worth finding out about the story behind it all. Not only do you get the history you get to walk part of the 'Nakasendo Highway' which in itself is a stunning walk through the mountains and experience nature in Japan.