Burg Hardenberg, Medieval castle ruins in Velbert, Germany

Burg Hardenberg is a castle ruin in Velbert featuring a rectangular layout with rounded corners. The site is surrounded by a moat and protected by a ring wall that survives in parts today.

Built in the 11th or 12th century as the seat of the Lords of Hardenberg, the castle burned in the 13th century but remained in use until the 15th century, as pottery shards from the 12th to 15th centuries show. In December 1354 Heinrich von Hardenberg sold the castle and his lordship for 6,000 marks in Brabant currency to Gerhard I of Berg, and the lords moved their seat to Hardenstein.

The castle carries the name of its original lords and still displays the typical layout of a medieval fortress today. Visitors can trace this arrangement in the preserved ring wall and the surrounding moat.

Above ground the castle site survives only as a hill and ditches in the terrain, about 600 metres southwest of Schloss Hardenberg. The excavation of 1888 exposed a roughly square area with rounded corners, a ring wall and a moat on three sides, entered from the east over a bridge. The 2023 survey found damage from illegal digging for rock crystals and from motorbikes and mountain bikes, which are banned.

The 1888 dig led by architect Gerhard August Fischer first exposed the square keep, 25 m tall with 10 m sides and 2.5 m thick walls of regular bossed ashlar. A 2023 survey by the Rhineland heritage office confirmed his findings but also recorded damage from illegal digging for rock crystals in the masonry and from motorbikes and mountain bikes ridden on the site.