Heuneburg is the site of a large early Iron Age (Hallstatt culture) hill fort near Riedlingen, Württemberg, in Germany.
The fort occupies a strategic site on a spur overlooking the River Danube, with a single line of earth ramparts and a counterscarp (outer bank) facing the level approaches from the west.
The occupants of the hill fort had strong links with the Mediterranean, importing amphorae of wine and exotic pottery from the Greek colony of Massilia, modern day Marseilles. During the 6th century BC the defences of the fort were remodelled along the lines of Greek fortresses, with mudbrick bastions on stone foundations. It has been suggested that this represents the Celtic city of Pyrene mentioned by Herodotus (Book 2:33).
The hill fort was destroyed in the later 6th century BC and then rebuilt with three circuits of walls. Several high status burial barrows dating to the same period are located at nearby at Hohmichele. The fort was also destroyed early in the 4th century BC, as the older Hallstatt culture gave way to the newly dominant La Tene peoples.
The site was abandoned until the early medieval period when its strategic importance was rediscovered.