Chiprovtsi Monastery is a Bulgarian Orthodox monastery 5 kilometres northeast of the town of Chiprovtsi in Montana Province in northwestern Bulgaria. It belongs to the diocese of Vidin and lies in the valley of the Ogosta river.
According to Petar Bogdan, the monastery was built in the 10th century and remained a religious and cultural centre despite Tatar and Magyar raids in the 13th century, the Ottoman invasion in the 14th century and Michael the Brave's raids in the 16th century. The monastery has been razed six times, in 1412, 1688, 1806, 1828, 1837 and 1876, with the one of 1688 after the Chiprovtsi Uprising being particularly devastating. The current monastery church was built in 1829.
The Chiprovtsi Monastery consists of a church dedicated to Saint John of Rila, residential buildings, a small graveyard and a three-storey tower featuring an ossuary, a chapel and a belfry.
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.