It is also known as  together with the – segment of the Hisatsu Line. Between 1916 and 1923 this line was part of the original rail connection from Kokura to Miyazaki, until the opening of the Nippo Main Line.
It is also designated as  in conjunction with the – segment of the Hisatsu Line. Between 1916 and 1923, this line was an integral component of the initial railway link between Kokura and Miyazaki, until the opening of the Nippo Main Line.