Burg Werle, Medieval castle ruins in Kassow, Germany

Burg Werle is a former Slavic castle site near Werle, northwest of Güstrow by the Warnow. No walls survive: the spot is now an artificially raised mound topped by a roughly six-tonne granite boulder placed there in 1856.

Built around 600 by local Slavs, Werle became the seat of the princes of Werle and was probably abandoned in the 13th century. In 1160 Henry the Lion took the hard-fought castle by a ruse and killed the Slavic prince Niklot. His sons Pribislaw I and Wertislaw regained it but had to give it up in 1163, when Wertislaw was captured defending it during Henry's punitive campaign; after peace it passed finally to Pribislaw I.

The granite boulder monument at Burg Werle serves as a reminder of the territorial transitions between Slavic and Germanic rule in Mecklenburg-Vorpommern.

The site lies near the Kassow district of Werle, northwest of Güstrow and close to the Warnow. What remains today is an artificially raised hill topped by a roughly six-tonne granite boulder placed there in 1856. No walls or information panels survive, so the mound and the stone are the only features to look for.

No walls survive at Burg Werle: the castle hill is an artificially raised mound, and the only object on it is a granite boulder of about six tonnes placed there in 1856. The Slavic stronghold itself was probably abandoned in the 13th century.