
The “iron church” St. Stephen in Istanbul has been designed by Armenian architect Hovsep Aznavor for the Bulgarian Orthodox Church in the 1890s. The architecture combines Neo-Gothic, Neo-Baroque and Neo-Byzantine influences. Since the ground close to the water was too unstable for a common masonry construction it was decided to build an iron church. After an international competition, the cast iron elements were manufactured by R. Ph. Waagner (today Waagner -Biro) in Vienna, preassembled there and then shipped through the Danube and the Black Sea to Constantinople. The outer walls, buried footings, window frames, door leaves, arches, columns, eaves and the roof were manufactured out of cast-iron sections, sheets and forged iron and connected to each other with bolts and nuts, rivets or welds. The total weight of all iron elements is only about 500 tons. The iron church was erected on 26 m long timber piles, completed in 1896 and inaugurated in 1898 by Exarch Joseph. The Sveti Stephan Bulgarian Church has been one of the sights of Istanbul throughout the decades. But as funds where short it could not be maintained and refurbished as required. A private foundation took the lead and where finally generously supported by the city of Istanbul with 3.3 Mio. Euro. Sveti Stephan underwent a fundamental renovation, which started under the Bulgarian-Turkish cooperation in 2011.

Previous works had already stabilised the foundations with soil improvement works including 282 jet grout piles. To bring the building in line with modern siesmic resistance standards, structural analysis and rectification was required. Accordingly, weak members were replaced, new ones added, and corroded columns were renewed as necessary. Altogether 88 tons of new structural steel elements were employed. The cast iron ornaments and interior panels were sand blasted and repaired as possible or reproduced and finally newly painted and mounted again. Also, the roofing was cleaned, and new zinc panels put in place. Bulgarian involvement was especially significant in the refurbushment of the iconostasis.

On 8 January 2018, Turkish President Recep Tayyip Erdogan and Bulgarian Prime Minister Boyko Borisov attended the inauguration of the renovated St. Stephen Bulgarian Orthodox Church in Istanbul, on the occasion of its 120th anniversary. Sveti Stephan is one of the world’s few surviving prefabricated cast iron churches and and remains one of the pearls of Istanbul. It is perhaps the most valuable Bulgarian cultural monument in Turkey.

| Project owner | Bulgarian Orthodox Churches Foundation, I·stanbul – S¸is¸li Istanbul Metropolitan Municipality | Vasil Liaze Yavuz Erkut, Hakan Genc |
|---|---|---|
| Location | Balat Mahallesi, Mürselpas¸a Cd. No:10, I·stanbul – Fatih I·stanbul – Fatih, TR | |
| Architect | Halil Onur Mimarlık Ofisi, I·stanbul – Fatih | Halil Onur |
| Structural Engineer | Kuram Mühendislik / Teori Mühendislik Ltd., Istanbul – Atas¸ehir | Taylan Akgün |
| Steel Contractor | S¸anlıbayrak Çelik Konstrüksiyon I·ns¸aat San. ve Tic. Ltd., Istanbul – Beylikdüzü | I·brahim S¸anlıbayrak |
| Main Contractor | Tas¸yapı I·ns¸aat Sanayi ve Ticaret Co. Inc. I·stanbul, TR | I·brahim Tas¸kın / Fikriye Bulunmaz |
| Date of Completion | January 2018 | |
| Steel Tonnage | 120 tons |
