Hikawa of Okutama, Tokyo
It is a popular day trip destination, however there are many nature trails with a number of waterfalls where you can enjoy the wilderness with few people. Okutama also has many great BBQ spots along the Tama River. The Hikawa area marked on the map is less than a 10 min walk from Okutama station, and it’s a great BBQ spot for train travelers.
Okutama is about 80 mins by direct train from Shinjuku station.