Lemberk Castle is located in the village of Lvová, part of Jablonné v Podještědí, west of Liberec. It was constructed in the 1240s by Havel of Markvartice. In the second half of the 16th century it was rebuilt into a Renaissance chateau and it acquired its present appearance after the mid-17th century under the lords of Breda. The last owners were the Clam-Gallas family, who owned the castle until 1945.
Today only the cylindrical tower is still standing from the original structure. The castle is now state owned and accessible to public in the form of organized tours.
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.