The road passes through the following municipalities: Turku – Lieto – Aura – Pöytyä – Loimaa – Humppila – Urjala – Akaa – Valkeakoski – Lempäälä – Tampere – Kangasala – Orivesi – Jämsä – Jyväskylä – Muurame – Jyväskylä (again) – Laukaa – Hankasalmi – Pieksämäki – Rautalampi – Pieksämäki (again) – Rautalampi (again) – Suonenjoki – Leppävirta – Kuopio – Siilinjärvi – Kuopio (again) – Tuusniemi – Outokumpu – Liperi – Joensuu – Tohmajärvi.

The Nokkakivi amusement park is located along the highway in Laukaa's Lievestuore between cities of Jyväskylä and Kuopio.

Even before the Winter War, road improvements had been started by straightening the worst bends, for example between Kangasala and Orivesi.

[4] 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.

[5] In 2000, the Helsinki-Tampere motorway was completed and a 9-way route was added: about eight kilometers of new roads were built north of Kylmäkoski to the north-west of Toijala, where 9-road joins Highway 3.