Should that be the area's name? I mean the stream is only in one part of the level, that'd be like calling F&H the pond because of that one area. As a whole the place seems more like a japanese Forest Mountain such as the valleys and smaller mountains around Mt. Fuji. Or a bamboo forest, how about calling it Mt. Yukumo since the whole thing resembles the Okutama valley around Fuji, down to the ruined shrines/village.