Designed by Gustave Eiffel (of Eiffel Tower fame). Eiffel never actually came to Santa Rosalia. Back in 1884 while still in France, he designed a prefabricated metal church, made entirely of stamped steel sheet squares for easy portability, as a prototype for missionary churches in France’s tropical colonies. After being displayed at the 1889 Paris World's Exposition, where it won first prize for church design, it was stored in a Brussels warehouse and almost forgotten, until an official with the Boleo Mining Company learned of it and had it shipped to Santa Rosalia as a place for the miners to worship.