Since the sign indicating the starting point of the river is located at the lower Nakatsu-gawa River, the source of the Kamogawa River may be believed to be the Nakatsu-gawa River; however, this is the case in the River Act, and traditionally, there are a great deal of people who regard Mt. Sajikiga-take as the source.
鴨川起点の表記は中津川下流域にあるため、これに従うと源流は中津川であると考えられるが、これはあくまでも河川法上での扱いであり、伝統的には桟敷ヶ岳を源流と見なす人も多い。