The Basilica of St. Severin is one of the twelve Romanesque churches of Cologne. St. Severin was established in the late 4th century as a memorial chapel and extended several times. The oldest parts of today's building date back to the 10th century.
The church has been extended and enlarged several times. On the passable archaeological dig area under the church in the midst of a Roman graveyard the foundation remains of the original building can be viewed.
St. Severin still owns rich furnishing: the murals in the crypta, the choral equipment with a part of the medieval floor, the original choir seating and the high altar, behind which the Shrine to the Holy Severin is shown, so that the believers could walk under it.
The forked crucifix from the 14th century and the late Gothic glass paintings in the long nave are also remarkable. The external impression is primarily Gothic as only the choir chancel remained Romanesque.
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.