It is possibly the largest prefabricated cast iron structure in the world.

The Bulgarian St. Stephen Church in Istanbul is the largest prefabricated cast iron structure in the world.

After this church burnt down, the iron church was built in its place.

Bulgarian St. Stephen Church

Iron was chosen in lieu of concrete because of the weak ground conditions.

The construction plans were prepared by the Istanbul-based Ottoman Armenian architect Hovsep Aznavur.

Photo:Resul Muslu | Dreamstime.com

The interior of Bulgarian St. Stephen Church.

Bulgarian St. Stephen Church

The Bulgarian St. Stephen Church wasnt the first prefabricated cast iron church, but it was certainly the largest.

Eventually, economies of scale reduced their cost to less than a quarter towards the end of the century.

Many of these churches survive to this day.

Bulgarian St. Stephen Church

Tin Tabernacle in Ballywillin.

Photo:Nick/Flickr

Tin tabernacle at Sandling, Kent.

Bulgarian St. Stephen Church

Tin Tabernacle in Ballywillin

Tin tabernacle at Sandling, Kent.