Gherla Fortress (Martinuzzi Fortress) built in the Renaissance style, is located on the right bank of Someşul Mic river, in Gherla. It is documentary attested from the year 1540, being built by the order of the bishop of Oradea, Gheorghe Martinuzzi, treasurer and governor of Transylvania.
The fortress was built according to the plans of the architect Domenico da Bologna, as a quadrilateral with defense bastions at the corners, surrounded by thick walls and a water ditch, and the entrance and exit of the fortress was made on a drawbridge, with access through underground tunnels.
Over time, the fortress belonged to several noble families, including the princes of Transylvania, Sigismund Báthory and Gheorghe Rákóczi II. As it was no longer of strategic importance, emperor Joseph II transformed Gherla fortress into a central prison for Transylvania. In 1913 the prison was transformed into a juvenile prevention institute, where children studied and learned various professions.
During communism, Gherla prison experienced two distinct periods: one period between 1945-1964 as a political prison, and the other between 1964-1989 as a prison for common law prisoners. After 1989, Gherla prison, one of the oldest in Romania, became a maximum security penitentiary.