Burg Winterstein, Medieval castle ruin in Waltershausen, Germany.

Burg Winterstein is a castle ruin near Waltershausen in Thuringia, built from stone with visible Gothic pointed arches and a half-timbered building standing among the remains. The site sits at approximately 370 meters elevation and occupies a maintained park that preserves its structures.

The Wangenheim lords established this fortified water castle in 1307 to strengthen their power in the region. Major renovations took place in 1513, but the complex suffered serious damage during the Thirty Years War.

A local legend tells of a dog named Stutzel who carried love letters to Gotha during the Thirty Years' War and was buried here after the couple he helped married in 1630. Ludwig Bechstein recorded a different version in his Thüringer Sagenbuch, where the dog belonged to a court huntsman and was buried at Friedenstein Castle.

The site lies at 370 metres in the centre of Winterstein, a district of Waltershausen. The grounds hold a local history room (Heimatstube) and a Haus des Gastes, and the Vogtei building was lived in until the end of the 18th century. A second castle site, the Sommerstein, stood at the southern edge of the village, where only a ditch remains visible today.

A local legend tells of a dog named Stutzel who carried love letters to Gotha during the Thirty Years' War and was buried here after the couple married in 1630. Ludwig Bechstein recorded a different version in his Thüringer Sagenbuch, where the dog belonged to a court huntsman and was buried at Friedenstein Castle.