Isatsu-gawa River begins in the south of Mt. Misen (664 m above sea level) on the border between Maizuru City, Kyoto Prefecture, and Ayabe City, and runs into Maizuru Bay through the Nishi-Maizuru urban area.
京都府舞鶴市と綾部市の境にある弥仙山（標高664m）の南に源を発し、西舞鶴市街地を通り舞鶴湾へ注ぐ。