Denmark–Sweden border

The current national border between Denmark and Sweden dates to 1658.

It is entirely a maritime border, along Kattegat and Øresund, and in the Baltic Sea between Bornholm and Scania. The territorial waters (12 mile zone) of the two countries meet exclusively along the Øresund, extending to about 115 kilometres (71 mi), approximately between Höganäs and Falsterbo. There is one road connection, the 16 kilometres (9.9 mi) long Øresund fixed link, opened in 2000, besides a number of ferry links.

Sweden and Denmark–Norway became separate countries with the breakup of the Kalmar Union in 1523. Until 1658, the historic provinces of Scania, Blekinge and Bohuslän (and until 1645 also Halland) belonged to Denmark, so that the Denmark–Sweden border ran across what is now southern Sweden. In 1645 and 1658 respectively, these provinces were ceded to Sweden in the Treaty of Roskilde, establishing the Øresund as national boundary.

The modern Norway–Sweden border remained the border between Denmark–Norway and Sweden until the breakup of Denmark and Norway in 1814. The modern Denmark–Sweden border then became the border between the Union between Sweden and Norway and Denmark until the breakup of Sweden and Norway in 1905. It became a border of German-occupied Europe from 1940 to 1945 (Denmark was still a country although under practical control by Germany).

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Wikipedia