The Ayalon River (Hebrew: נחל איילון‎, Nahal Ayalon, Nahr el barideh or Wadi Musrara, in Arabic) is a perennial stream in Israel, originating in the Judean Hills and mouthing into the Yarkon River in the Tel Aviv area. The total length of Ayalon River is about 50 kilometres and it drains an area of 815 square kilometres. The river flows through the Shephelah region, from the Judean Hills within Ayalon Valley, near the Ben Gurion Airport, along Ayalon Freeway and mouths with the Yarkon River in Bavli Quarter in Tel Aviv.