Ruine Lichtenfels, Medieval castle ruins in Zwettl, Austria

Ruine Lichtenfels is a medieval castle on a peninsula in Lake Ottenstein, surrounded by the Kamp River's waters. The remains include partially preserved stone walls and foundations, with the old chapel structure still visible.

Hartung von Rauheneck and his sons Albero, Otto and Ortlof are documented in this area in 1136; Hartung received it as a fief from Duke Heinrich Jasomirgott and built the castle in the mid-12th century. The Rauheneck family, nicknamed 'die Tursen' (the giants), held the fief until 1335. During the Hussite wars of 1427/28 the castle sheltered the treasures and library of Zwettl Abbey. After 1623 it passed to private owners and was abandoned by its last resident in 1804.

The castle's name Lichtenfels is not documented in the sources as 'field of light'; the sources give no etymology. What visitors can notice today is the chapel of Saint Paul, the only surviving structure, which remained a popular pilgrimage destination into the last century. The ruins belong to the parish of Friedersbach in the Zwettl municipality.

The ruins are best observed from the dam bridge, which offers an unrestricted view of the structure. The area around the lake has swimming facilities and camping grounds that complement a visit.

Only the castle chapel, dedicated to Saint Paul, survives today; it remained a popular pilgrimage destination into the last century. The rest of the complex fell into ruin after its last resident left in 1804.