Nestled along the shores of the Golden Horn in Balat, St. Stephen of the Bulgars (Bulgar Church), widely known as the Iron Church, is one of Istanbul’s most remarkable religious landmarks. Built in 1898, this stunning church is unique in its entirely prefabricated cast-iron construction, making it one of the few remaining iron churches in the world. Designed by Austrian architect Hovsep Aznavur, its ornate neo-Gothic façade and elaborate interior details were produced in Vienna, shipped to Istanbul in pieces, and assembled on-site, creating an architectural wonder that blends industrial craftsmanship with spiritual devotion. The church holds great historical significance for the Bulgarian Orthodox community, as it symbolized their independence from the Greek Orthodox Patriarchate in the 19th century. After extensive restoration work completed in 2018, the Iron Church once again shines with its golden domes and intricate stained-glass windows, making it a hidden gem for visitors interested in history, architecture, and religious heritage in Istanbul.