Hikawa Gorge is a natural formation at the confluence of the Nippara (日原川) and Tama Rivers (多摩川), easily accessible from Okutama Station on the Okutama Mukashi Michi (奥多摩むかしみち — Okutama Old Trail). The gorge lies just a few kilometers downstream of the Oguchi Dam which forms Lake Okutama, the source of the Tama River.
The gorge is a popular vacation spot throughout the summer, with picnicking along the banks, but the fall colors in late October and early November bring out the best in the scenery.
Hiking the Okutama Mukashi Michi is just a bit challenging, with some climbing and rocky paths that can turn slick in wet weather. We arrived following a late-season typhoon and found ourselves clambering over mud and rocks that had washed over the path where a tree had fallen down the slope. But the trail is well marked and for the most part well maintained, with many beautiful scenes along the way.
From Shinjuku, the Chuo Line leaves about twice per hour, with a change at Oume (青梅). There is a “Holiday Express” runs direct a couple of times a day. It saves making a transfer, but takes the same time of about 1 hour 40 minutes to reach Okutama Station.