In the road numbering system of 1938, the route from Turku through
Huittinen, Tampere and Jämsä to Jyväskylä was numbered as road 9. The route of the road has changed significantly since these times. Initially, the road followed partly the same route as Highways
2 (from
Vampula to Huittinen),
11 (from Huhijärvi in
Mouhijärvi to Tampere) and
3 and
12 (from Tampere to Huutijärvi in Kangasala). Even before the
Winter War, road improvements had been started by straightening the worst bends, for example between Kangasala and Orivesi. The rehabilitation of the section between Huutijärvi and Orivesi in Kangasala was completed through work projects for the unemployed in 1953–1955, but when completed the road no longer met the requirements of increased traffic. At the end of the 1950s, a four-way intersection was formed on Lake Huutijärvi after the completion of the road through
Sahalahti and
Kuhmalahti to
Kuhmoinen (now regional road 325). In the early 1960s, the gap between Orivesi and Jämsä was significantly adjusted. The road was lined from
Längelmäki's Länkipohja to Jämsä directly, when the old road circled through the village of Halli,
Kuorevesi. However, even this road turned out to be narrow and winding before traffic picked up. The first 14-kilometer highway section between Turku and the Lieto station area was completed in 1967. The intersection of Highways 2 and 9 in Huittinen's Mommola, which became known for numerous traffic accidents, was converted into a level crossing in the same year. In 2000, the
Helsinki-Tampere motorway was completed and the route was re-adjusted: about eight kilometers of new roads were built north of
Kylmäkoski to the north-west of
Toijala, where Road 9 joins Highway 3. The journey between Turku and Tampere was extended by a few kilometers but 19 kilometers of new motorway section were created. The old road from Kylmäkoski to
Lempäälä was numbered 190. In 2001–2003, the road between Orivesi and Jämsä and between
Korpilahti and Muurame was significantly improved. The orientation of the road was improved by leveling hills and straightening bends, the road was widened, medium-railed bypass lanes and game fences were built on it, as well as new bridges and level crossings. In 2010, Highway 9 was extended from
Kuopio to the
Niirala border station by connecting Highway 17 and Main Road 70 as part of it. ==Sources==