Sønderborg (Danish pronunciation: [ˈsønɐˌbɒːˀ] - (German: About this sound Sonderburg ) is a Danish town of Region of Southern Denmark. It is the main town and the administrative seat of Sønderborg Municipality (Kommune). The town has a population of 27,434 (1 January 2014),[1] in a municipality of 75,264.


Sønderborg Castle

The town of Sønderborg is home to Sønderborg Castle (Sønderborg Slot), the Royal Danish Army's Sergeant School (until 2013) and Sandbjerg Estate (Sandbjerg Gods). Sønderborg castle is in the centre of the town, and houses a museum focusing on the history and culture of the area. The museum is open all year. Sandbjerg Estate, which had belonged for many years to the Dukes of Sønderborg, and then to the Reventlow family, was donated to Aarhus University in 1954. In addition Sønderborg has a castle-like barracks built by the German military in 1906, placed centrally by Als Fjord, opposite Alsion (see picture below).

The old part of Sønderborg is on the island of Als, but some of its western suburbs have spread onto the mainland of Jutland into what had been the interior of the fort of Dybbøl.


Prior to the Second Schleswig War of 1864, Sønderborg was situated in the Duchy of Schleswig, a Danish fief, so its history is properly included in the contentious history of Schleswig-Holstein. In the 1920 Schleswig Plebiscite that returned Northern Schleswig to Denmark, 43.8% of the city of Sønderborg's inhabitants voted for the cession to Denmark and 56.2% voted for remaining part of Germany.[2]


University of Southern Denmark

Both University of Southern Denmark and University College South (Danish: University College Syd) have a branch in Sønderborg.


The town of Sønderborg lies on both sides of Alssund; the narrow strait between these two sides is called Als Strait (Alssund). Two road bridges connect the city across the strait: the 682-meter Als Strait Bridge (Alssundbro), built in 1978-1981; and the 331-meter King Christian X's Bridge (Kong Christian Xs Bro), built in 1925-1930.


Danfoss is in Nordborg, 25 km from Sønderborg


The city is served by Sønderborg Airport.

Notable natives

KRH Sonderborg, 1962
Ludvig Harboe
Else Roesdah, 2012

Arts & Science

Public ideas



Lars Christiansen, 2007
Simon Poulsen, 2011

Panoramic view

Panoramic photo taken from Sønderborg Castle towards the harbour.


Musical Institutions

Sønderborg is home to the South Jutland Symphony Orchestra [1], link to Official Site Sønderjyllands Symfoniorkester.


Sønderborg Castle is today a museum about the history of Southern Denmark.


External links

Media related to Sønderborg at Wikimedia Commons