Erdenburg: An Iron Age Hillfort in Germany
Site at a Glance
- Rating
- 4.3
- Popularity
- Very Low
- Country
- Germany
- Primary era
- Iron Age
- External website
- Open
- Eras represented
- Iron Age
- Civilizations
- Unclassified
- Site type
- Military
- Remains
- Fort
On this page7 sections
History
Erdenburg is an Iron Age hillfort in Bergisch Gladbach, Germany, associated with a Celtic or Celtic-influenced Germanic community in the territory of the Ubii. Its construction was initially placed in the Late La Tène period, the later Iron Age of much of temperate Europe, around the first century BC, although later radiocarbon readings have left the precise date uncertain. The fortification was already in existence by the Roman period and was not built in response to conflicts with Rome.
The 1935 excavation and its interpretation
Excavations at Erdenburg in 1935 were organized and financed by the Waffen-SS, the military and paramilitary arm of the SS under Nazi Germany. Archaeologists Werner Buttler and Hans Schleif conducted the work and initially dated the fortification to the Late La Tène period. The interpretation was shaped by Nazi ideology, which presented Erdenburg as a Germanic defensive work built against the Romans and attributed it to the Sugambri, an ancient Germanic community associated with the area between the Lippe and Ruhr rivers.
This attribution was later regarded as untenable because the Sugambri lived north of the Ubii, while Erdenburg stood in Ubian territory. The Ubii were an ancient community whose lands lay along the Rhine and extended, in the historical reconstruction used here, from the Ruhr region toward the lower Lahn. Their connections with Rome further weakened the idea that Erdenburg had been constructed as an anti-Roman stronghold.
Radiocarbon dating and historical reassessment
In 1968, Hermann Schwabedissen, a professor of prehistory and early history at the University of Cologne, examined charcoal from a fire layer at the base of the rampart. Radiocarbon dating, which estimates the age of once-living material by measuring its remaining radioactive carbon, produced a result of 310 ± 80 BC. A 2012 record of an archaeological conference held by the Landschaftsverband Rheinland, or LVR, states that Schwabedissen may later have withdrawn this result orally and instead described the date as 90 ± 50 BC. The age of the fortification therefore remains uncertain.
The scale of the enclosure and the labor required to construct its ramparts point to centrally organized communal work. Erdenburg has consequently been interpreted as a refuge for people from the surrounding area. Its extensive view toward and beyond the Cologne area also allows for possible defensive or watch functions. At the same time, the limited excavation trenches leave the question of permanent stone or timber buildings unresolved, so the site’s precise pattern of occupation cannot be defined with certainty.
Mining damage and archaeological protection
The eastern approach lay in the area of the Jungfrau mining pit. Removing the pit destroyed the ring ramparts on that side. At the end of the 1935 excavations, Nazi forced laborers and local companies artificially reconstructed the damaged ramparts, leaving the eastern remains partly shaped by modern intervention rather than by their original deterioration alone.
The monument is listed as Ringwall Erdenburg, number 5, in the register of archaeological monuments of Bergisch Gladbach. Its archaeological importance lies not only in the surviving earthworks, but also in the changing interpretation of the site, from an ideologically framed anti-Roman stronghold to a fortification whose date, community, and function require more cautious assessment.
Remains
Erdenburg occupies a ridge and enclosed an oval area measuring approximately 230 by 165 metres. Three concentric ditches surrounded the enclosure, each about two metres deep. The defenses used timber reinforcement, and the inner rampart was probably constructed as a timber-framed structure divided into rectangular compartments filled with earth. This technique is known as a murus Gallicus, a rampart made with timber framing or compartments filled with earth or stone.
Ramparts, ditches, and entrance
The main entrance was positioned on the western side of the enclosure. From there, the concentric ditches and timber-reinforced ramparts formed the principal defensive system around the ridge. Their scale required substantial communal labor and helps explain the interpretation of the fortification as a refuge or as a place with defensive and watch functions.
The northeastern side presents a different physical condition. The ramparts there are flattened or have been lost, and the enclosure is no longer closed in that area. The reason is unknown. A drawing from the 1935 excavation shows the middle rampart as continuous at this point, while long-term erosion from rain, water, and wind may have progressively lowered the earthworks. The eastern approach was additionally affected by the removal of the Jungfrau mining pit, after which the damaged ramparts were artificially reconstructed.
Interior evidence and present condition
Excavation inside the enclosure has not established a permanent building layout. The trenches were limited, and stone foundations may therefore remain untested in other areas; timber buildings could also have escaped recognition because their locations are generally identified through postholes. This uncertainty allows the refuge interpretation to remain plausible without excluding more substantial occupation. The surviving fortification is consequently a combination of ancient earthworks, eroded sections, and ramparts altered by mining damage and later reconstruction.
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