Aggstein Castle is one of the most famous castles in Austria and fascinates visitors of all ages. The legendary castle ruins are on a ledge of rock 300 m above the Danube, which drops away precipitously on three sides. The castle was probably built in the early 12th century by Manegold III of Acchispach (Aggsbach). In 1181 it came into the possession of the Kuenring family of Aggsbach-Gansbach. It was besieged and conquered in 1230/31 during the revolt led by Hadmar III and his vassals against Duke Frederick II of Austria. In controversies over the succession of Frederick II, or herrscherlosen Zeit ("time without a ruler"), the Kuenring changed position a few times. Leutold Kuenring thus defeated the Austrian nobility in the revolt against Duke Albert: subsequently, the castle was besieged and in turn conquered in 1295/96. The last Kuenring, Leutoldo II, kept the castle from 1348 to 1355. It later fell into disrepair.
In 1429, Duke Albert V assigned the castle to his chamberlain, Jörg (Georg) Scheck von Wald. Albrecht commissioned him to rebuild the ruined castle to ensure the passage of ships on the Danube. In 1438 Scheck von Wald received toll rights for ships going up the river. In return, he had to maintain the towpaths from which the upstream barges were pulled. He also built a toll booth on the river bank which now serves as a forest house. Over time, he became a robber baron, raiding ships on the Danube. Hence his nickname, "Schreckenwald", (pun on his family name, Scheck von Wald, meaning "Forest of Terror"), which is said to have been given to him due to his cruelty to the population. In 1463 the castle was again besieged by another robber baron, Georg von Stain. He defeated Scheck von Wald and took over the castle as collateral, as the Duke was said to owe him money. In 1476 von Stain was expelled by Ulrich Freiherr von Graveneck who ruled the castle from 1476 to 1477, until he too was forced to surrender it.
In 1477 the duke Leopoldo III acquired the castle and occupied it with tenants and custodians to stop the raids. In 1529, the castle was razed to the ground by a group of Turks during the first Turkish siege of Vienna. Once again it was rebuilt and equipped with loopholes for artillery pieces.
In 1606 Anna Freiin von Polheim und Parz, the widow of the last tenant, bought the castle. After his death, the castle was badly neglected. In 1685 it was transferred to Count Ernst Rüdiger von Starhemberg, together with Schloss Schönbühel. Ludwig Josef Gregor von Starhemberg sold the properties to Count Franz von Beroldingen in 1819. It remained in the possession of von Beroldingen until 1930, when the Schönbühel estate, together with the ruins of Aggstein Castle, was sold to Count Oswald von Seilern Aspang.
Hadmar III is said to have considered the castle impregnable. In fact, there is no evidence that the castle was ever stormed directly by force. Only other measures, such as siege hunger, led to the conquest of the castle.
