Burg Steyerberg, Castle site in Steyerberg, Germany

Burg Steyerberg consists of medieval fortress ruins positioned on the southern slope of Knappsberg hill, sited roughly 1 kilometer southwest of Deblinghausen with the Große Aue river below. The remaining foundations display traces of regional medieval construction methods.

The castle was built by the Counts of Hoya on the Knappsberg to guard their territory against the Bishops of Minden, and was first documented in 1259. Destroyed around 1285 by the Minden bishop, it was retaken and rebuilt by Count Gerhard of Hoya in 1293, then pawned in 1305 for 600 marks of Bremen silver. In the 14th or 15th century the castle was moved to an island in the Große Aue; that later site was destroyed in 1519 during the Hildesheim Diocesan Feud.

A narrow ravine with stone steps, the Hexentreppe, leads up to the former castle site on the Knappsberg. Local legend says witches climbed it from the Große Aue valley on Walpurgis Night to light a hidden fire on the summit, and their shrieking was sometimes heard in Steyerberg.

No walls, towers or foundations survive on the Knappsberg; only the natural terrain and erosion gullies remain, so there is nothing built to examine. The climb follows the narrow ravine with its stone steps, the Hexentreppe, up to the summit. The Große Aue flows below the western slope.

Stone from the original fortress was repurposed in 1550 to build the Amtshof administrative building in Steyerberg. This shows how materials from the destroyed castle were recycled into later local structures.