Špilberk Castle in Brno, Czechia, atop a hill overlooking the city. It served being a royal castle ahead of becoming transformed into a fortress while in the 13th century. Špilberk was the heaviest prison while in the Austro-Hungarian Empire, earning the nickname “Dungeon of Nations” for imprisoning political dissidents. Good https://rent03578.wikijm.com/790508/what_does_flat_mean