Altena

This article is about the German town. For the Dutch municipality, see Altena, North Brabant. For the Dutch village, see Altena, Drenthe. For other uses, see Altena (disambiguation).

Altena
Town
View of Altena Castle in September 2008
Coat of arms
Location of Altena within Märkischer Kreis district
Location of Altena
Altena Location within Germany Altena Location within North Rhine-Westphalia
Coordinates: 51°18′N 07°40′E
Country	Germany
State	North Rhine-Westphalia
Admin. region	Arnsberg
District	Märkischer Kreis
Subdivisions	7
Government
• Mayor (2025–30)	Guido Thal (CDU)
Area
• Total	44.42 km2 (17.15 sq mi)
Highest elevation	511 m (1,677 ft)
Lowest elevation	145 m (476 ft)
Population  (2025-12-31)
• Total	16,403
• Density	369.3/km2 (956.4/sq mi)
Time zone	UTC+01:00 (CET)
• Summer (DST)	UTC+02:00 (CEST)
Postal codes	58741–58762
Dialling codes	02352
Vehicle registration	MK
Website	www.altena.de

Altena (German pronunciation: [ˈaltəna] ^ⓘ; Westphalian: Altenoa) is a town in the district of Märkischer Kreis, North Rhine-Westphalia, Germany. The town's castle is the origin for the later Dukes of Berg. Altena is situated on the Lenne river valley, in the northern stretches of the Sauerland.