一いっ級きゅう河か川せん

noun

class A river; first-class river

A river designated by the Japanese government as especially important for national land conservation and the economy, subject to direct national management.

• 利と根ね川がわは日本にほん最さい大だいの一いっ級きゅう河か川せんです。

  The Tone River is Japan's largest class A river.

• 一いっ級きゅう河か川せんの管かん理りは国