Schloss Altenberg, Baroque castle in Hitzendorf, Austria

Schloss Altenberg is a Baroque castle in Hitzendorf featuring four corner towers positioned prominently on a hillside. The structure separates the main area of Hitzendorf from the neighboring community of Berndorf.

Franz Anton von Haydegg built the castle at the end of the 17th century on a site known since the 16th century as the Altenberg farmstead. In 1740 the Haydegg family had to sell the castle and all its possessions. Anton Schellenbauer acquired the estate in 1790, was ennobled in 1794, and lost the title when he was arrested for fraud in 1817; the property then passed to the Haffner family of Graz.

The castle's name comes from the Altenberg farmstead recorded on this site since the 16th century, before Franz Anton von Haydegg built the Baroque schloss at the end of the 17th century. A local legend holds that the ghost of former owner Anton Schellenbauer wanders the castle park on stormy nights; in fact he was arrested for fraud in 1817 and died in 1829 in a penal institution.

The castle underwent major renovation work in 1976 to preserve its structure and adapt it for private residential use today. The exterior can be viewed from the surrounding grounds, though the interior is closed to the public.

The castle operated as a restaurant from the 1960s to 1972, serving as a gathering place for locals and visitors. This period shows how the building played different roles in the community before becoming a private residence.