Gherla Fortress (Martinuzzi Fortress), built in Renaissance style, is on the right bank of Somes Mic river, in Gherla municipality. It is documentary mentioned in 1540, being built at the order of the Bishop from Oradea, Gheorghe Martinuzzi, treasurer and governor of Transylvania.
The fortress was erected according to the plans of the architect Domenico da Bologna, under the form of a quadrangle with defence bastions in the corners, surrounded by thick walls and a water ditch and the entrance and exit from the fortress was made on a mobile bridge, existing also the access through underground tunnels.
During the time, the fortress belonged to many aristocratic families, including to the Transylvanian princes, Sigismund Báthory and Gheorghe Rákóczi II. Because it no longer had strategic importance, the emperor Josef II transformed Gherla fortress in central prison for Transylvania. In 1913 the prison is transformed in prevention institute for minors, where children studied and learned different professions.
During the Communism, Gherla prison had two different periods: the years 1945-1964 – political prison, namely the years 1964-1989 – prison for common law prisoners. After 1989 Gherla prison, one of the oldest from Romania, became a maximum security penitentiary.