Graz-Karlau Prison serial killer Wolfgang Ott; and the terrorist Tawfik Ben Chaovali, who was involved in the Rome and Vienna airport attacks. Graz-Karlau Prison Graz-Karlau Prison () is located in Gries, the 5th district of the city of Graz, capital of the Austrian state of Styria. With a capacity of 552 inmates, Graz-Karlau is the third largest prison in Austria. Built between 1584 and 1590 in late Renaissance style to designs by Antonio Tade and Antonio Marmoro, it was used as a summer hunting residence for Archduke Karl II of Austria. Originally, it was called "Dobel Castle". The German word "Dobel" is
Graz since 1551, and displays over 30,000 items. From the earlier part of the 15th century, Graz was the residence of the younger branch of the Habsburgs, which succeeded to the imperial throne in 1619 in the person of Emperor Ferdinand II, who moved the capital to Vienna. New fortifications were built on the Schlossberg at the end of the 16th century. Napoleon's army occupied Graz in 1797. In 1809, the city withstood another assault by the French army. During this attack, the commanding officer in the fortress was ordered to defend it with about 900 men against Napoleon's army of