Altschlossfelsen, Cultural heritage monument in Palatine Forest, Germany

Altschlossfelsen is a 1,500-metre-long rock wall of bunter sandstone on the Brechenberg near Eppenbrunn, rising up to 30 metres. Its layered face is reddish-brown below and grey-brown above, split by a vertical cleft into a taller right-hand mass and a left-hand column, with moss and lichen on the weathered ledges.

Finds from the Hallstatt and Roman periods, including Latène pottery sherds discovered in 1964, show early use of the rocks. On the four main rocks are traces of an 11th- or 12th-century castle: a stepped structure, post holes, masonry remains and beam slots. A four-metre-wide hollow may have served as a cistern; the castle is not mentioned before 1297 or in the 1605 border description.

The name Altschlossfelsen, "Old Castle Rocks", recalls the medieval castle whose traces remain on the four main rocks: a stepped passage, post holes, masonry and beam slots. A four-metre-wide hollow on one rock may have served as a cistern. The rock wall lies on the German-French border, and a footpath at its base leads to Roppeviller in Lorraine.

The rocks can only be reached on foot; allow an hour from Eppenbrunn on the German side or from Roppeviller in France. Paths run along the foot of the wall and link to the Altschlosspfad, Grenzweg and Helmut-Kohl-Wanderweg. Narrow trails climb to the plateau, and a viewpoint on the southern rock looks into the French Wasgau.

The rock face shows a "rock glow" (Felsenglühen): in the first half of April, around 19:00, the low sun lights the southeast side of the third rock from Eppenbrunn; in the morning it appears around 8:45. A four-metre-wide hollow on one rock may have served as a cistern for the medieval castle.