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.
This railway section is also known as  along with the – portion of the Hisatsu Line. From 1916 to 1923, it formed a vital part of the original route connecting Kokura and Miyazaki, prior to the introduction of the Nippo Main Line.