This small church on Rüütli street has been the spiritual home for generations of Estonian Swedes, an ethnic group that's been present in Tallinn since the Middle Ages. The location had originally been an almshouse for the city's poor, but in 1733 the tsarist government gave it to the Swedish congregation, which been left without its own church since the Great Northern War.
During Soviet times the building was converted into a sports hall and fell into disrepair, but was renovated and reconsecrated in 2002. It now has a congregation of around 200, and continues to hold services in Swedish. In addition to its Baroque altar by Joachim Armbrust and a Baroque pulpit, the church has a unique baptistery created by famed sculptor Christian Ackermann in 1680.
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.