The Tama River (多摩川, Tama-gawa) is a major river in Yamanashi, Kanagawa and Tokyo Prefectures on Honshū, Japan. It is officially classified as a Class 1 river by the Japanese government. Its total length is 138 kilometres (86 mi), and the total of the river's basin area spans 1,240 square kilometres (480 sq mi). The river flows through Tokyo, on the dividing line between Tokyo and Kanagawa. In the city, its banks are lined with parks and sports fields, making the river a popular picnic spot.