Landštejn Castle, Medieval castle ruin in South Bohemia, Czech Republic.

Landštejn Castle is a ruin of pale, weathered masonry whose walls rise to varying heights, the tallest forming an L-shaped block at the rear with a flat grassy terrace inside its roofless interior. A lower polygonal wall encloses a courtyard with a small circular depression and scattered rubble, and rectangular window openings pierce the walls, some empty and some small and deep-set. The Romanesque chapel and the main wall with two towers survive from the original layout.

The castle was probably founded by King Přemysl Otakar I as a counterweight to the older Zöbing castle at Pomezí; the oldest part is documented in 1231, when Hartlieb of Landštejn witnessed a deed. In 1381 King Wenceslas IV granted it to Konrad Kraiger von Kraigk, and in 1420 Jan Žižka besieged it. A lightning-set fire destroyed it in 1771, after which it was abandoned and its masonry quarried by nearby villages.

The castle grounds served as a filming location for the 1999 film Joan of Arc, where the battle scenes of the attacks on Orléans and Paris were shot. Friedrich Schiller set his 1781 play The Robbers in the surrounding landscape.

The ruin stands at 656 metres on a hill above the village of Landštejn, about three kilometres northwest of Staré Město pod Landštejnem. It has been open to the public since 1990 and is managed by the National Heritage Institute. The surviving masonry includes the main wall and the Romanesque chapel.

The castle was used as a filming location for the 1999 film Joan of Arc, with battle scenes of the attacks on Orléans and Paris shot there. Lightning struck the castle in the 1660s and knocked down the corner of one of the Romanesque towers.