Arad fortress was built on the Left Bank in Mures closed at the request of Empress Maria Theresa. Designed by Ferdinand Philipp Harsch Vauban-style Tenaille has star shape with six corners, was provided with three rows of pillboxes underground and more rows of trenches, which could be flooded. The work took 20 years (1763-1783) and was executed thousands of prisoners. Inside the main gate and buildings were built in Baroque style. Inside the fortress there in a Catholic church and surrounding buildings were hosted Franciscan monks. By 1918 the city was one of the largest military prisons of the Austro-Hungarian Empire. During the Hungarian revolution of 1848-1849 under the republican army besieged and bombarded the city garrison town every day for nine months. In the summer of 1849 garrison occupied the Hungarian revolutionary army, but after 46 days, Russian and Austrian armies and forced to surrender. 500 revolutionary army officers, were imprisoned in the Arad fortress, most of them sentenced to death. In July 1919 the Romanian army took the city. In the future the city will become a museum complex.