The Venetian Castle is an extension of the Byzantine Fortress of Durrës. Built in the sixth century, it was considered as one of the most powerful fortresses along the western coast of the Adriatic. Architectonic elements of the structure and historic records show that the fortress was rebuild in the first half of the fifteenth century, when Durrës was ruled by the Republic of Venice.
In the middle Ages, the design of the fortress was constantly dictated by the advances in the art of fortifications, assault tactics and weaponry of the time. Hence, by the time that artillery was widely used in fortresses, the Venetian Castle was built to do just that.
The tower is built upon a circular plane 9 meters in diameter and 9.6 meters tall. It rises above a cone – shaped basement and bounded in its highest section by a semi – arched stone frame. The basement is filled with earth mound paved in stone slabs, thus making it the only floor in the tower that serves as a defensive podium circled by a serrated banquette.
There is just one hall inside the tower and it is lit by five artillery pill – boxes. It is covered by a spherical dome built with bricks.
The walls measure 3.70 meters thick reinforced by a wooden sash. Because the walls were so thick, it was possible to build a cylindrical stair up to the roof and numerous small slots used as ammunition depot.