Map illustrating how the current highway/beltway Kehä III ('Ring III') around Helsinki was built to follow the path of the medieval Kuninkaantie ('King's road') – or Suuri Rantatie ('The Great Coast Road') – that used to connect the cities of Turku and St. Petersburg, used by Swedish kings from the 14th century. The background map illustrates the area during the years 1958–1962, before the construction of the beltway.
 Kehä III after 2012. Dashed line is Vuosaaren satamatie (fi), an extension not strictly part of Kehä III, opened for traffic in 2015.
 Kuninkaantie in 1870–1907, to the intersection of the road to Porvoo. Dashed line follows old roads to Westerkulla manor, not part of Kuninkaantie.
Own work

Kehä III: Topographic map series 1:100000 / NLS National Land Survey of Finland (CC BY 4.0)
Kuninkaantie: Senate Atlas (1870-1907), Senaatin kartastot / National Archives of Finland (CC BY)
Background: Basic maps 1:20 000, Old printed maps / NLS National Land Survey of Finland (CC BY 4.0)
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