Autumn country visit

I am considering a visit to enjoy fall and the change of leave in the countryside. Can you suggest somewhere in particular that is famous for this? I have lived in the Tokyo/Yokohama area and visited Hokkaido, so somewhere other than those areas.
Is mid October too late?
Thanks
Camy

You can consider NIkko, which is a pretty destination a couple of hours by train from Tokyo. The colours of the mountains and the trees during fall, when we were there last year , is amazing.The bonus of course is the world heritage sites in Nikko. Late October or early November would be ideal.
Best.
Dhiraj