Dosan Line is a Japanese railway line ,operated by Shikoku Railway Company, between Tadotsu Station in Tadotsu, Kagawa prefecture and Kubokawa Station in Shimanto, Kochi prefecture iin Shikoku.
The first section of the line, between Tadotsu and Kotohira, opened in 1889.
The whole line was completed in 1951.
Dosan Line connected Kochi to Tadotsu across Shikoku Mountains and Sanuki mountains , and has connected Kubokawa through the inland along the Tosa bay.
In the Japanese National Railways era, it was called” Dosan Main Line”, but the JR Shikoku revised the track name to “Dosan Line “in 1988 after its privatization.
The special express trains of Nanpu run between Okayama and Kochi, Nakamura, or Sukumo.
The Shimanto special express are operated between Takamatsu and Kochi, Nakamura, or Sukumo.
The former run 14 laps a day and the latter run 5 laps a day.