Rydboholm Castle (Rydboholms slott) dates back to the Middle Ages. The castle, with the three interconnected wings around an open courtyard, dates from the 16th century. The main building was built in 1548. The castle was reconstructed during the 18th century. Southwest of the castle is a large park in English style from the early 19th century, built by Magnus Fredrik Brahe.
From the 15th century, Rydboholm was the property of members of the Sture family, followed by the Vasa dynasty and later the Brahe family. According to some sources Gustav I of Sweden, who was King of Sweden from 1523 until his death, was born at Rydboholm Castle. From 1520, it belonged to his sister, Margareta Eriksdotter Vasa.
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.