Ehrenfels Castle, Medieval hillside castle ruin in Rüdesheim am Rhein, Germany

Ehrenfels Castle is a ruined hillside castle on the steep eastern bank of the Rhine above Rüdesheim am Rhein. Its north side is closed by a 4.6-metre-thick, 20-metre-high shield wall with two 33-metre corner towers; the three-storey palas stands on the river side, and a courtyard with a cistern lies between them. The outer bailey survives only as foundations.

The Archbishop of Mainz commissioned the castle in 1212 to defend the region against attacks. The structure became part of a broader strategy to control this important river region.

The toll post itself stood down at the river and worked together with the Binger Mäuseturm; the castle above housed the Burgmannen who controlled shipping. The grape variety Ehrenfelser, bred in 1929 at Geisenheim, takes its name from the ruin, and vineyards still surround it.

The ruin is reached from Rüdesheim on a hiking trail through the vineyards. The interior is closed by locked gates, so there is no walk around the courtyard; access inside is only possible on guided tours booked in advance. Because breeding peregrine falcons nest here, the castle can otherwise be viewed only from outside.

A grape variety called Ehrenfelser was named after this castle and grows on the vineyards surrounding it. The name reflects how closely the castle's history is tied to winemaking in this region.