Castle of Gjirokastra stands among the Balkans' most impressive fortresses, perched on a hilltop with commanding panoramic views over the city. Archaeological evidence dates its origins to the 3rd or 4th century BC, though documented Byzantine references appear from 1336, with substantial walls likely erected in the 12th century. The Ottomans captured the fortress in 1419 and significantly expanded it during Ali Pasha of Tepelenë's rule in the late 18th and 19th centuries, adding the iconic clock tower. Today's fortress hosts two museums within its extensive grounds, including weapon and history exhibits, along with a prison museum established on the site of the former King Zog I prison built in 1932.