The remains of the castle can be visited
Schell-Pyrmont Castle

Schell-Pyrmont Castle, today called Schellenburg, is the remnant of a hilltop castle at 305 m above sea level on the Schellenberg near the town of Bad Pyrmont in the district of Hameln-Pyrmont in Lower Saxony.
The castle was built around 1184 on behalf of the Archbishop of Cologne Philipp von Heinsberg, who had received his property from Emperor Frederick I (Barbarossa), to secure the Emmer valley towards the Weser. Not only his officials and castellans, but also the Counts of Schwalenberg-Pyrmont resided in the castle as vassals. After a feud from 1250 to 1255 between the Archbishop of Cologne and the Pyrmont Counts, the noble lords of Lippe came to the castle from 1262, to whom the destructions of 1267/77 and 1284 are also attributed.
In 1824, the Schellenturm (Schellen Tower) was erected on the Schellenberg from the remains of the castle. Today, the former castle complex shows minor rubble stone wall remains, extensive ramparts, and rubble mounds.
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Location: 52.0027, 9.2768