Kegnæs

Høruphav is a small town located on the island of Als in south Denmark, in Sønderborg Municipality. Before 2007, the town was the seat of the Sydals Municipality.

Augustenborg Municipality - Until 1 January 2007 Augustenborg was a municipality (Danish, kommune) in South Jutland County on the island of Als off the east coast of the Jutland Peninsula in south Denmark. The municipality covered an area of 53 km2, and had a total population of 6,577 (2005). Its latest mayor was Åse Nygaard. The site of its municipal council was the town of Augustenborg. Augustenborg Municipality ceased to exist due to Kommunalreformen ("The Municipality Reform" of 2007). It was combined with former Broager Municipality, Gråsten Municipality, Nordborg Municipality, Sundeved Municipality, Sydals Municipality, and Sønderborg Municipality to form the new Sønderborg Municipality. This created a municipality with an area of 499 km2 and a total population of 49,886 (2005).

Augustenborg (German: Augustenburg) is a town on Als Island in Sønderborg Municipality, Region of Southern Denmark in Denmark. The town lies at the head of Als Fjord. To the east is the Little Belt. Ferry service connects Augustenborg to the island of Funen from the nearby town of Fynshav. Augustenborg has a population of 3,160 (1 January 2023). It was the main town of Augustenborg Municipality until its merger into Sønderborg Municipality in 2007.

Augustenborg Palace (or Augustenborg Castle; Danish: Augustenborg Slot, German: Schloss Augustenburg) is a Rococo-style palace in the southwestern part of Augustenborg, Als Island, Denmark, overlooking Augustenborg Fjord. The palace owes its name to Duchess Auguste (1633–1701). Augustenborg gave its name to the House of Schleswig-Holstein-Sonderburg-Augustenburg, the last member of which was Duke Christian August II (1798–1869).

German submarine U-2521 was a Type XXI U-boat (one of the "Elektroboote") of Nazi Germany's Kriegsmarine, built for service in World War II. She was ordered on 6 November 1943, and was laid down on 31 August 1944 at the Blohm & Voss yard at Hamburg, as yard number 2521. She was launched on 18 October 1944, and commissioned under the command of Oberleutnant zur See Joachim Methner on 21 November 1944.

Gelting Bay (German: Geltinger Bucht, Danish: Gelting Bugt), sometimes also the Bay of Gelting, is a bight of the Baltic Sea on the northeastern coast of the region of Anglia at the exit to the Flensburg Fjord near the town of Gelting. The bay extends from Habernis in the northwest via Wackerballig to the south to the nature reserve of Geltinger Birk in the east. The length of the shoreline along the bay is about 15 kilometres. There are currently no commercial shipping routes across the bay. The coastal region belongs to the district of Geltinger Bucht with its head office in Steinbergkirche. The land around Gelting Bay is dominated by agriculture and tourism, the bay itself by sailing and some fishing.

The Battle of Als (Danish: Slaget om Als; German: Übergang nach Alsen) was fought on 29 June 1864 during the Second Schleswig War between Denmark and Prussia. It was the last major engagement of the war, as the Prussians under General Herwarth von Bittenfeld secured the island of Als – occupied by 9,000 Danish troops, including the garrison of Dybbøl which had retreated there – in a night attack masterminded by the Chief of Staff (later Field Marshal) Leonhard Graf von Blumenthal.

Als (Danish pronunciation: [ˈælˀs], German: Alsen) is a Danish island in the Baltic Sea.

German submarine U-733 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 13 October 1941 at the Schichau-Werke yard at Danzig, launched on 5 September 1942, and commissioned on 14 November 1942 under the command of Oberleutnant zur See Wilhelm von Trotha.

German submarine U-794 was a Type XVIIA U-boat of Nazi Germany's Kriegsmarine during the Second World War. She was one of a small number of U-boats fitted with Hellmuth Walter's high test peroxide propulsion system, which offered a combination of air-independent propulsion and high submerged speeds. She spent the war as a trials vessel and was scuttled on 5 May 1945 in Gelting Bay. U-794 was built by Friedrich Krupp Germaniawerft, Kiel. The keel was laid down on 1 February 1943, the boat was launched on 7 October. She was commissioned on 14 November. The Feldpost Number was M 52 496. U-794 did not undertake any combat patrols and was instead assigned as a trials boat at first to the 5th U-boat Flotilla, followed by the 8th U-boat Flotilla, before returning to the 5th flotilla for the rest of the war. In late March 1944, Admiral Karl Dönitz and four other admirals took part in a trial of U-794. Although they were enthusiastic, the boat, designed for high underwater speed (over 20 m.p.h.) was difficult to manoeuvre, and the keel to beam ratio was too high.

German submarine U-721 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 16 November 1942 at the H. C. Stülcken Sohn yard at Hamburg, launched on 23 July 1943, and commissioned on 8 November 1943 under the command of Oberleutnant zur See Otto Wollschläger.

Sønderborg (Danish pronunciation: [ˈsønɐˌpɒˀ]; German: Sonderburg [ˈzɔndɐbʊʁk] ) is a Danish town in the Region of Southern Denmark. It is the main town and the administrative seat of Sønderborg Municipality (Kommune). The town has a population of 28,137 (1 January 2023), in a municipality of 74,380. In recent times, Sønderborg is a center for trade, tourism, industry, and education in the region of Southern Denmark. The town is the headquarters for several industrial companies. Sønderburg joined the UNESCO Global Network of Learning Cities in 2016.