The is Japaneserailway line between Kaifu Station, Kaiyō and Kannoura Station, Tōyō. Together with JR ShikokuMugi Line, it has the official nickname . This is the only railway line operates. The company is abbreviated as . Since the line goes through sparsely popurated area, it is in the severe business condition. It is discussed whether to continue the railway line or not.
Japanese National Railways started the construction of Asa Line in 1959. The portion of it opened as Mugi Line in 1973, while the construction of other parts halted in 1980. The construction resumed under Asa Kaigan Railway, the newly founded third sector company. The eastern portion of the line, now called Asatō Line, opened in 1992. The western portion of the planned Asa Line opened as Tosa Kuroshio RailwayAsa Line in 2002. The complete Asa Line, however, never came into reality.