Ottenstein Castle rises impressively above the Ottenstein Reservoir in the scenic Waldviertel region of Lower Austria, its origins tracing to the 12th century. First documented mention of the Ottenstein family appears in 1177, with the castle likely predating written records. The fortress endured two failed sieges during the Thirty Years' War in 1622 and 1640, testament to its strong fortifications. Among its most treasured features is a Romanesque castle chapel featuring vaulted ceilings adorned with monumental frescoes dating to approximately 1170, representing exceptional medieval religious artistry. The castle now operates as both a hotel and restaurant, serving as a cultural venue for antique fairs, art exhibitions, and special events. Visitors enjoy guided tours exploring the castle's medieval heritage, maintain manicured gardens, and access hiking trails and outdoor activities throughout the surrounding landscape.