Iwamizawa Station - in 1882 the Hokkaido government opened an 11 km line to Mikasa, known as the Horonai line.
In 1888 a 7 km extension to Ikushunbetsu and ~3 km branch line from Mikasa to the Horonai coal mine opened, and the line was sold to the Hokkaido Coal Co. in 1889.
The line was nationalised in 1906, and closed in 1987.
At Ikushunbetsu a forest railway comprising a 15 km 'main line' and a 3 km branch opened in 1938, and closed in 1955 to allow for the construction of the Katsurasawa dam.

Bibai Station;
- The 3 km branch to Minami-Bibai opened in 1931 to service a coal mine, closing in 1973.
Passenger services operated 1944-71.

- The Mitsubishi Mining Co. (MMC) opened an 8 km line to Sumiyama mine in 1914, extending the line 3 km to Tokiwadai in 1924.
The line closed when the mine closed in 1972.
The MMC also operated a 2 km line from Chashinai Station to a coal mine 1952-67.

Naie Station - The Mitsui Mining Co. operated a 5 km line to Higashi Naie 1949/51 to 1968.

Sunagawa Station;
- The Mitsui Mining Co. also opened the 7.3 km branch to Kamisunagawa in 1918.
The line was nationalised in 1926, with passenger services introduced the same year.
The line closed in 1994.

- A 15 km branch to Utashinai, opened by the Hokkaido Coal Co. in 1891, nationalised in 1906 and closed in 1988.

Fukagawa Station - The first section of the Shinmei line to Nayoro on the Soya Line opened in 1924, opening to Nayoro in 1941 and closing in 1995.
A 51.2 km line was proposed from Shumarinai on that line to Chikubetsu on the Hoboro line north of Rumoi with construction commencing in 1959.
A substantial steel truss bridge was constructed before work was abandoned in 1962.
Iwamizawa Station - in 1882 the Hokkaido government opened an 11 km line to Mikasa, known as the Horonai line. In 1888 a 7 km extension to Ikushunbetsu and ~3 km branch line from Mikasa to the Horonai coal mine opened, and the line was sold to the Hokkaido Coal Co. in 1889. The line was nationalised in 1906, and closed in 1987. At Ikushunbetsu a forest railway comprising a 15 km 'main line' and a 3 km branch opened in 1938, and closed in 1955 to allow for the construction of the Katsurasawa dam.
Bibai Station;
- The 3 km branch to Minami-Bibai opened in 1931 to service a coal mine, closing in 1973. Passenger services operated 1944-71.
- The Mitsubishi Mining Co. (MMC) opened an 8 km line to Sumiyama mine in 1914, extending the line 3 km to Tokiwadai in 1924. The line closed when the mine closed in 1972. The MMC also operated a 2 km line from Chashinai Station to a coal mine 1952-67.
Naie Station - The Mitsui Mining Co. operated a 5 km line to Higashi Naie 1949/51 to 1968.
Sunagawa Station;
- The Mitsui Mining Co. also opened the 7.3 km branch to Kamisunagawa in 1918. The line was nationalised in 1926, with passenger services introduced the same year. The line closed in 1994.
- A 15 km branch to Utashinai, opened by the Hokkaido Coal Co. in 1891, nationalised in 1906 and closed in 1988.
Fukagawa Station - The first section of the Shinmei line to Nayoro on the Soya Line opened in 1924, opening to Nayoro in 1941 and closing in 1995. A 51.2 km line was proposed from Shumarinai on that line to Chikubetsu on the Hoboro line north of Rumoi with construction commencing in 1959. A substantial steel truss bridge was constructed before work was abandoned in 1962.
Hakodate Main Line