The medieval Tumbo church is very well-preserved. It was built in a Romanesque style in the 1100s. The sacristy and porch were added in the 15th century. The original tower was collapsed in 1734 and the new one was built couple of years later.
The pulpit was made in 1630. The sandstone-made font date from the 1100s and polyptychs date also from the Middle Ages.
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.