Burg Alt-Lichtenstein, Medieval castle ruins in Lichtenstein, Germany.

Burg Alt-Lichtenstein is a castle ruin sitting on a steep rocky cliff edge of the Swabian Jura at approximately 800 meters elevation. The remains include partial walls, defensive fortifications, a water collection system, and stone steps cut into rock that connected different levels of the site.

Built between 1150 and 1200, probably under Gebhard von Lichtenstein, the castle was first destroyed in 1311 by Reutlingen troops in the imperial war against Count Eberhard I of Württemberg and rebuilt in 1315. Reutlingen razed it again between 1377 and 1381 in the Swabian War of the Cities. In 1389 it passed to Württemberg as a ruin and was never rebuilt; the Lichtenstein line died out in 1687.

The ruins display medieval military architecture through visible foundation stones and fortification walls that reveal how defenders once organized their space. Visitors can trace the layout of former buildings by studying these structural remains.

The ruin lies on a steep rock spur of the Swabian Jura at 800 m, 500 m southeast of Schloss Lichtenstein above Honau. Access is via stone steps cut into the rock; the terrain is steep and not wheelchair accessible. The walls were excavated in the 1990s and can be visited; there is no artificial lighting, so go in daylight.

The 15.4-metre shield wall survives only as a ruin: its 4.3-metre-thick masonry is fragmentary, with small patches of the original stone facing still visible on the wall and the tower-like structure behind it. Cut into the rock, steps lead from the inner courtyard up to an outer rock terrace.