Deutsch-Altenburg Castle is a privately owned historic fortress located in Bad Deutsch-Altenburg, a spa town situated on the right bank of the Danube River in Lower Austria's Bruck an der Leitha district. The castle sits within a region of significant historical importance, adjacent to the Danube-Auen National Park, where the landscape shaped by the river provides a rich backdrop for exploring medieval structures and former imperial residences. While the castle itself is not open to public access due to private ownership, its presence contributes to the cultural heritage of the area, standing as a testament to centuries of Austro-Hungarian aristocratic history along the Danube valley.