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