Burg Birkenfeld, Medieval castle in Maroldsweisach, Germany.

Burg Birkenfeld is a ruined castle in Birkenfeld in the Rhineland-Palatinate, Germany. Of the medieval Sponheim castle, later rebuilt as a Renaissance palace, only small parts remain: the gatehouse, now a private dwelling, and the so-called viewing tower, which looks out over Birkenfeld and the Schwarzwälder Hochwald.

The fortress was first documented in 1293 and quickly became an important administrative center for the region. It underwent various ownership changes and structural modifications that shaped its architecture over the centuries.

The name Birkenfeld comes from a Frankish settlement noted for its birch trees, recorded in 981 though the place existed around 700. The castle itself appears as "Berkenvelz" in a 1293 charter. The surviving gatehouse, now a private dwelling, bears a cartouche with the names of 11 soldiers from Burg Birkenfeld killed in World War I and the inscription "Steh Enkel und lies mit Ehrfurcht die Namen".

Burg Birkenfeld lies in the town of Birkenfeld in Rhineland-Palatinate, not in Bavaria. Only fragments survive: the gatehouse, now a private residence, and the so-called viewing tower, which looks out over Birkenfeld and the Schwarzwälder Hochwald. Large information boards at the entrance and a carved wooden panel in the gateway passage explain the site's history.

The preserved gatehouse was fully renovated by private owners and now serves as a dwelling. Above the gate, a cartouche lists the names of the eleven soldiers from Burg Birkenfeld who fell in the First World War, with the inscription "Steh Enkel und lies mit Ehrfurcht die Namen". A carved wooden information panel stands in the passage.