Finnish national road 1

This article does not cite any sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Finnish national road 1" – news · newspapers · books · scholar · JSTOR (October 2021) (Learn how and when to remove this message)

You can help expand this article with text translated from the corresponding article in Finnish. (March 2009) Click [show] for important translation instructions. View a machine-translated version of the Finnish article. Machine translation, like DeepL or Google Translate, is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-translated text into the English Wikipedia. Do not translate text that appears unreliable or low-quality. If possible, verify the text with references provided in the foreign-language article. You must provide copyright attribution in the edit summary accompanying your translation by providing an interlanguage link to the source of your translation. A model attribution edit summary is Content in this edit is translated from the existing Finnish Wikipedia article at [[:fi:Valtatie 1]]; see its history for attribution. You may also add the template {{Translated|fi|Valtatie 1}} to the talk page. For more guidance, see Wikipedia:Translation.

National Road 1
Valtatie 1 (Finnish) Riksväg 1 (Swedish)
Route information
Part of E18
Maintained by the Finnish Transport Agency
Length	165 km (103 mi)
Major junctions
From	Helsinki
To	Turku
Location
Country	Finland
Major cities	Espoo, Lohja, Salo
Highway system
Highways in Finland

The Finnish national road 1 (Finnish: Valtatie 1 or Finnish: Ykköstie; Swedish: Riksväg 1) is the main route between the major cities of Helsinki and Turku in southern Finland. It runs from Munkkiniemi in Helsinki to the VI District of Turku, and is part of the European route E18. The road is a motorway for its whole length.

The first portion of the motorway was constructed in the 1960s between central Helsinki and Kehä III, and extended to Lohjanharju in the 1970s. In the other end of the road, the motorway stretches from eastern Turku to Lahnajärvi near Suomusjärvi. In 2005, a portion of motorway between Lohjanharju and Lohja was opened. The last part of the motorway (Lahnajärvi–Lohjanharju) was opened on January 28, 2009. This part of motorway contains five tunnels totalling 5.2 kilometres (3.2 mi). The longest tunnel (2,230 m or 7,320 ft, double-bore) is also the second longest road tunnel in Finland.