This is a must, if you have the time and the money. A couple of days in this area is certainly worth the expense in time and money. There is a beautiful shrine in Nikko which unlike Ise and Izumo is extremely decorative. Interesting walks along the river to the “abyss”.
Take the Shinkansen to Tokyo and change at Ueno station to the JR Nikko line to Nikko. Or from Tokyo station take the Yamoto Line to Ueno and then the subway to Asakusa station and there change for the Tobu-Nikko Line for Nikko. You may have to change at Shimo-Imaichi. The limited express is a wonderful train but the views are not very exciting. Figure three and a half hours to Tokyo and two more to Nikko.
While you are at Nikko keep on going. A short bus ride up a very winding road is the town of Chuzenjiko Onsen. A real Japanese tourist spot in season. If you go there out of season it is empty, so stay away from Japanese holidays. This is a really beautiful spot for nature lovers. Lakes, riverse, waterfalls, lots of trails in the woods. Most hotels will have hot spring baths.
From Nikko, take a bus going to Chuzenji or to Yumoto Spa. Get off at Chuzenjiko Onsen. Right there will be Kegon Falls and a rope way to a good view of the mountains and lake. The falls are wonderful. From the bus stop you can go right or left around the lake. If you go left you will pass hotels and restaurants and eventually come to a shrine. Keep following the shore of the lake and pass summer houses of various countries. If you go to the right you will pass hotels and restaurants but once out of town you can walk forever. Pick up the “Salamander Trail” (I actually saw one!). This will take you right along the shore of the lake until you come to a ferry boat landing. From there follow the highway and on the right you will come to another waterfall. Follow the river upstream along a very delightful trail. You will come to an area that opens up into a mountain meadow. Beautiful views of the surrounding mountains. Flowers everywhere, in season. Eventually there will be another waterfall with some shops at the base. Walk up the right side of the waterfall and you will come to another lake. Stay to the right and you will come to Yumoto, just a collection of hot spring hotels. Look for the temple and you will find a swamp with hot springs. This is a long walk but very easy going. Give yourself about five hours, including many stops to eat and take photos. Then take the bus back to Chuzenji or Nikko.