Rivers are not used for navigation in Japan due to their state in the map where they contain more waterfalls which are unnecessary for navigation.
Kakita River is the shortest Class 1 river in Japan.
The Arakawa River, the Asa River (Japan), the Edo River, the Kanda River, the Katase River, the Naka River (Saitama Tokyo), the Shakujii River, the Sumida River, the Tama River, and the Tsurumi River.
Shinano river
shinano river is the longest rive river japan
Japan
It is located in Russia not Japan.
Lake sumida is the longest river in Japan
It is a river in Japan, and it refers to a planned dam on the river of the same name.
japan
no its in japan
shinano