Tanigawadake is one of the most popular mountains for climbers.
After a 10-minute ropeway ride from Doaiguchi Station at the foot of the mountain, take the lift to Tenjin Pass. From Tenjin Pass, it takes about two and a half hours of walking along the ridge to reach the summit.
At the foot of the mountain there are gentle paths and you can enjoy walking with nice views of the valley and mountain streams.
http://www.tanigawadake-rw.com/tanigawadake/
Tambara Shitsugen is known as “Little Oze”, where visitors can observe marshland plants in each of the four seasons.
It takes about two hours to get there from the center of Tokyo, and the main pathway begins near the parking lot and takes about one hour to walk, so it can be enjoyed by all ages. If you walk a little further, you will come to “Beech Flat”, a forest of giant beech trees.
https://www.numata-kankou.jp/activity/nature/tanbara_shitsugen/index.html
Oze is a famous mountain wetlands area located at the shared border of Gunma, Niigata, Fukushima. The lengthy wooden pathways are well maintained and hiking in Oze can be really refreshing. It is a nice place to spend 2 or 3 days, but a one day trip from Tokyo is not out of the question.
https://www.env.go.jp/en/nature/nps/park/oze/index.html
https://www.pref.gunma.jp/04/e23g_00065.html
https://www.japan-guide.com/e/e7440.html
