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Traditional Swedish units of measurement were standardized by law in 1665, prior to which they only existed as a number of related but differing local variants. The system was slightly revised in 1735. In 1855, a decimal reform was instituted that defined a new Swedish inch as 1⁄10 Swedish foot (2.96 cm or 1.17 inches). Up to the middle of the 19th century, there was a law allowing the imposition of the death penalty for falsifying weights or measures. After a decision by the parliament in 1875, Sweden adopted the metric system on 22 November 1878, with a ten-year transition period until 1 January 1889.
As part of the transition, the Swedish mil measurement was maintained, but was shortened from 18000 alnar – the equivalent of 10.69 km (6.64 mi) – to exactly 10 kilometres (6.2 mi). This measurement is still in use in both Sweden and Norway (which were in a union at the time).
Old length units
The Swedish units of length included the following:
aln – "forearm" (cf. ell) (pl. alnar). After 1863, 59.37 centimetres (1.948 feet). Before that, from 1605, 59.38 cm as defined by King Carl IX of Sweden in Norrköping 1604, based on Rydaholmsalnen.
fot – "foot", 1⁄2 aln. Before 1863, the Stockholmfot was the commonly accepted unit, at 29.69 cm (0.974 ft).
kvarter – "quarter", 1⁄4 aln.
tum or verktum – "inch", 1⁄6 kvarter or 1⁄12 fot, making it 2.47 centimetres (0.97 inches).
linje – "line", after 1863 1⁄10 tum, 2.96 mm (0.117 in). Before that, 1⁄12 tum or 2.06 mm.
mil – "mile", also lantmil. From 1699, defined as a unity mile of 18000 alnar or 10.69 km (6.64 mi). The unified mile was meant to define the suitable distance between inns. After the 1889 metric conversion the Swedish mil is defined as exactly 10 kilometers.
nymil – "new mile" from 1889, 10 km exactly. Commonly used to this day, only referred to as mil.
kyndemil – the distance a torch will last, approx 16 km (9.9 mi).
skogsmil, rast – distance between rests in the woods, approx. 5 km (3.1 mi).
fjärdingsväg – 1⁄4 mil.
stenkast – "stone's throw", about 50 m (164 ft), used to this day as an approximate measure.
rev – 160 fot, for land measurement, was 100 fot after 1855.
stång – 16 fot, for land measurement.
tum – "thumb" (inch), 1⁄12 fot, 2.474 cm (0.974 in). After 1863 decimaltum, 1⁄10 fot, 2.96 cm, not much accepted by professional users in mechanics and carpentry who later switched to English inch (2.54 cm, abandoned only late 20th century) and metric system.
tvärhand – "hand", 4.0 in.
Old area units
kannaland – 1000 fot, or 88.15 m (948.8 sq ft)
kappland – 154.3 m (1,661 sq ft).
spannland – 16 kappland
tunnland – 2 spannland or 4,937.6 m (53,148 sq ft), about 1 acre
kvadratmil – Square mil, 36 million square favnar, from 1739.
hektar - 100x100m, still commonly used for land area of farms.