Fužine Castle is Ljubljana's has retained its original Renaissance character. It was built by a crossing point over the Ljubljanica river's rapids between 1528 and 1557 on commission from the wealthy local merchants Veit Khisl and Hans Weilhaimer, the former of whom served several terms of office as Mayor of Ljubljana. A defence tower was built in each of the four corners of the castle building and another one over the entrance, which is accessible via a stone bridge across the moat surrounding the castle. Inside the castle there are remains of Renaissance and Baroque wall paintings, and on the wooden ceiling of the castle chapel a fragment of a ceiling painting.
During its history the castle has housed an iron smelting works, a smithy, a glassworks and a paper pulping mill, and served as ancillary premises of a power plant. Since 1992, when it was thoroughly renovated by the architect Peter Gabrijelčič, it has been occupied by the Museum of Architecture and Design.
References: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.