The two lines were merged into one in 1931, renamed as Muroran Main Line.

The two lines were merged into a common operating company, Ystads Järnvägar.

On 21 February 1898, the lines were merged.

Griscom believed that the major lines should be merged to control capacity and avoid rate wars.

This line was later merged into the Western Union Railroad Company.

After several months, the lines were merged to allow through service, and the TRR station was closed.

These lines were merged it into the Y&MV.

The lines were nationalized in 1927, and merged into one, becoming the Hidaka Line.

Meanwhile, in December 2006, lines 3 and 6 were merged into the present line 3.

On 25 September 1989, line 5 was merged into line 6.