Ali Pasha Castle is named after Ali Pasha of Tepelenë who resided there until 1820. The current fortress was rebuilt in 1819 from its surface with 3 towers.
Built under Venetian dominion in the late 15th or early 16th century, it provided a stronghold for the Venetians on Corfu to exploit fishing, grazing, olives and timber in and around Butrint. The castle was the centrepiece of numerous conflicts with the burgeoning Ottoman Empire, and changed hands on several occasions. It was finally destroyed by a retreating French army in 1798 to prevent it falling into the hands of Ali Pasha.
The fortification attributed to Ali Pasha at Butrint lies some 2.4 kilometres due west at the mouth of the Vivari Channel. This in itself began life in the late 17th or early 18th century as a fortified estate centre belonging to a Corfiote family that farmed land on the plains south of the ancient city. Ali Pasha seized control of the structure around 1804 and carried out a series of defensive improvements including the installation of gun batteries. Given its small size it is unlikely that the fort functioned as anything more than a control over access from the sea to Butrint, and it can not be compared to Ali's more redoubtable fortresses in the region at Tepelena, Gjirokastra and Ioannina.
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The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.