Schleswig[dead link] (Danish: Slesvig) is in Schleswig-Holstein. The region around the city of Schleswig was a major centre during the Viking Age. The original viking settlement Hedeby and the Dannevirke defensive wall are on the UNESCO World Heritage List.
One of the northernmost cities in Germany, Schleswig was part of the Duchy of Schleswig that was ruled by the Danish king until the 1864 German-Danish war in which Prussia and Austria defeated Denmark, annexing Schleswig and Holstein. A dispute over the administration of those two territories would trigger the 1866 Prussian-Austrian war and in 1870/71 Prussia would lead the German states (sans Austria) into a war against France leading to the first unified German state under Prussian leadership.
54.4979.569291Hedeby(Haithabu).The remains of an ancient Viking settlement, which is now considered the most important archaeological site of Schleswig-Holstein. There is a museum and reconstructed houses where you can learn about the history of Hedeby and the everyday life of the Vikings.(updated Jul 2018)
54.48319.49822Danevirke.Literally meaning the Earthworks of the Danes, the first of these walls were constructed already around 500 AD as a protective wall against the south. A few centuries later, it was expanded by the Vikings into a system of trenches and walls. Interestingly, the Danevirke was used in the war against Prussia in 1864 when the Danes lost the area.(updated Jul 2018)
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