Bunkenburg

The Bunkenburg was a low-lying ringwall fortification that stood on the Aller river opposite Ahlden during the 13th and 14th centuries. Its name almost certainly derives from its building material: Raseneisenstein, a locally quarried porous ironstone known colloquially as 'Bunke', pointing to the distinctly regional construction methods used along the Aller in the Middle Ages. Today only a single earthwork remnant survives — roughly 60 metres long and 3 metres high — barely recognisable as a former fortification. For visitors interested in medieval defensive architecture or regional geology, the site offers a rare tangible trace of early medieval lordship in the Aller lowlands.