Fredevald, Castle ruin in the Lužické hory, Czech Republic

Fredevald is a castle ruin in Dolní Prysk featuring stone walls with Gothic-style pointed arches and ribbed vault elements. The structure sits at an elevated position offering views across the surrounding landscape.

Fredevald was probably founded by the Michalovic family in the second half of the 14th century and was first documented in 1406, when it belonged to Hynek Berka of Duba. In 1428 Heinrich Berka sold it to Siegmund of Wartenberg, whose men used it as a base for raids. In 1440 troops of the Lusatian Six Cities League besieged, captured and razed it; from the end of the 15th century it was deserted.

The name Fredevald was later replaced by Pustý zámek, Czech for "deserted castle", and German sources call it Wüstes Schloss. The ruin lies within the Pustý zámek nature monument, declared in 1963, and since 1890 a lookout platform on the summit has been maintained by the Česká Kamenice mountain association.

The ruins are reached via marked walking paths with informational signs explaining the architecture along the way. Visitors should expect uneven ground and come prepared for outdoor conditions at the elevated location.

The castle rock is made of phonolite columns up to 25 metres long that fan out across the slope, a record of Tertiary volcanism in northern Bohemia. The same rock continues on the far side of the Kamenice valley at Břidličný vrch. Blasting for the 19th-century road cut away part of the rock face.