A Scandinavian mile (Norwegian and Swedish: mil, [miːl], like "meal") is a unit of length common in Norway and Sweden, but not Denmark. Today, it is standardised as 10 kilometres (≈6.2 mi), but it had different values in the past.
The word is derived from the same Roman source as the English mile. In Sweden and Norway, the international mile is often distinguished as an "English mile" (engelsk mil), although in situations where confusion may arise it is more common for Scandinavians to describe distances in terms of the official SI unit kilometre.
In Norway and Sweden, the old "land mile" or "long mile" was 36,000 feet: because of the different definitions of foot then in use, in Norway this was 11,295 m and in Sweden 10,688 m. (Had the imperial foot been used, the distance would have worked out to 10,972.8 m.) The distance was equal to an older unit of measurement, the "rast" ("rest", "pause"), representing a suitable distance between rests when walking. See League (unit).
Historically the Scandinavian mile has also been defined as 10 verst. A verst is approximately 1.07 km or ~2/3 of an imperial mile. The Finnish virsta and Russian verst differ by approximately 2 metres.
When the metric system was introduced in Norway and Sweden in 1889 (the actual law having been passed in 1875), the mil was redefined to be exactly 10 km.
In 1887 the metric system was introduced to Finland. The traditional Finnish peninkulma, called mil in Swedish (that defined the same length), was then redefined to be exactly 10 km. In Finland, however, it has been much less in use than in Sweden. Peninkulma now has mostly literary use. Its most likely etymology is a mishearing of peninkuuluma (from peni, archaic for dog + kuuluma, approximately "to be heard") which meant the distance over which a dog's howl or bark could be heard. Another possible mishearing is peninkuorma but this may also have another meaning that is now lost, "dog's load" or the weight of goods that a dog can carry. A similar unit, penikoorem, was used in Estonia, defined as 7 versts.
The mil is currently never used on road signs and kilometre is the standard for most formal written distances. It is however very common in colloquial speech involving distances greater than 10 kilometres. The mil has however not lost all formal uses. Various tax deductions, for example regarding distance travelled for business purposes, are measured in mil by the Swedish Tax Agency (Skatteverket). It is also used in the most common unit for measuring vehicle fuel consumption – "litres per mil".
Naomi Mitchison, in her autobiographic book You may well ask, relates an experience during a walking tour in Sweden: "Over in Gotland I walked again, further than I would have if I had realized that the milestones were in old Swedish miles, so that my disappointing three-mile walk along the cold sea edge under the strange ancient fortifications was really fifteen English miles".