Of all the things to do in japan, Arashiyama Monkey Park is one of my most recommended. Get up close and personal while feeding the monkeys at Arashiyama, one of the great experiences in Japan.
As a volcanically active country, Japan is situated on a number of volcanoes and this volcanic activity naturally heats a number of water sources that pool aboveground, and from this natural occurrence, thousands of onsens have both occurred naturally and been stimulated by man-made structures.
All in all: if you’re visiting japan, try and make some time go to a ryokan and experience the historic culture and long-kept traditions of the local people. It’s a rich life experience and one I’m really glad that we got to undergo.