Judenburg is a historic town in Styria, Austria. Since 1 January 2012, it is the administrative centre of the newly established Murtal district. It has previously been the capital of the Judenburg District.
On 1 January 2015 the municipalities of Oberweg and Reifling were merged into Judenburg.
It is located in the Upper Styrian region, on the western end of the Aichfeld basin, stretching along the Mur River from Judenburg down to Knittelfeld in the east. The broad valley is bound by the Niedere Tauern range in the north and the Noric Alps (Lavanttal Alps) in the south.
The municipal area also comprises the cadastral communities of Tiefenbach and Waltersdorf, a former municipality incorporated in 1963.
Archaeological findings indicate that the area was settled at least since the days of the Celtic kingdom of Noricum. Judenburg itself was first mentioned in a 1074 staple right deed as mercatum Judinburch, a market town within the estates of Eppenstein Castle, the ancestral seat of the Bavarian Eppensteiner noble family, who ruled as Styrian margraves in the 11th century. The name literally means "Jews' Castle", referring to the town's origin as a trading outpost on the route from the Mur Valley across the Obdacher Sattel mountain pass to Carinthia, in which Jews played an important role, being represented in the city's coat of arms.
Bezirk Judenburg was a district of the state of Styria in Austria. On January 1, 2012 Judenburg District and Knittelfeld District were merged to Murtal District.
Suburbs, hamlets and other subdivisions of a municipality are indicated in small characters.