St. Stephen's Church is a protected cultural monument situated in Nitra. The beginning of the present-day church dates back to the 10th century. In the following two centuries, St. Stephen's Church was rebuilt. In early 18th century the church was renewed to its final Baroque style. This site is a rare medieval structure with the sanctuary beneath a Baroque semicircular vault with lunettes. You can still see parts of Romanesque frescoes inside. The church was rebuilt by František Maťašovský in 1720.
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.