Eltz Castle is a medieval castle nestled in the hills above the Moselle between Koblenz and Trier, Germany. It is still owned by a branch of the same family (the Eltz family) that lived there in the 12th century, thirty-three generations ago. Bürresheim Castle, Eltz Castle and Lissingen Castle are the only castles on the left bank of the Rhine in Rhineland-Palatinate which have never been destroyed.
The castle is surrounded on three sides by the river Elzbach, a tributary on the north side of the Moselle. It is on a 70-metre (230 ft) rock spur, on an important Roman trade route between rich farmlands and their markets. The Eltz Forest has been declared a nature reserve by Flora-Fauna-Habitat and Natura 2000.
The castle is a so-called Ganerbenburg, or castle belonging to community of joint heirs. This is a castle divided into several parts, which belong to different families or different branches of a family; this usually occurs when multiple owners of one or more territories jointly build a castle to house themselves.