Soon after the Pori line was built, plans were laid to build a line between Haapamäki and Saarijärvi. The Finnish Defence Forces and Members of Parliament from Central Finland stood behind the project because they felt that it was important and it would shorten the trip south of the Haapamäki-Jyväskylä line by 100 km, which would also make it possible to reach Tampere via Haapamäki without having to go through Jyväskylä first. The project was pushed by MP Taavi Vilhula and the proposal was quickly passed in Parliament. The line was marked out in the terrain at the end of the 1930s with one of the most important stations along the way being Multia, which was where MP Vilhula was from. The eruption of World War II, however, caused construction on the line to stop and the severe war reparations that Finland had to pay put a damper on further construction for a long time even once the war was over. The decision to build the line was finally shelved when plans to build a direct line between Jyväskylä and Jämsä were launched.