The oldest part of the Ösmo Church was constructed in the latter part of the 12th century. The church was modernized in the 14th century, when the old chancel was demolished and replaced by one which was both taller and wider. The church largely gained its present appearance during the 15th century.
The interior of the church is decorated with frescoes added just after the middle of the 15th century. It is said that they were painted by Albertus Pictor, the most famous church artists of the medieval period. The church also contains a large number of coats of arms used in processions, and a triumphal crucifix.
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.