I found these gems on Facebook. Here are the captions accompanying the photos.
Completed in 1891, San Sebastian Church is noted for its architectural features. An example of the revival of Gothic architecture in the Philippines, it is the only all-steel church or basilica in Asia. It has also been implausibly reputed to be the first prefabricated building in the world, and more plausibly claimed as the only prefabricated steel church in the world.
The prefabricated steel sections that would compose San Sebastian Church were manufactured in Binche, Belgium. According to the historian Ambeth Ocampo, the knockdown steel parts were ordered from the Societe Anonyme des Enterprises de Travaux Publiques in Brussels. In all, 52 tons of prefabricated steel sections were transported in eight separate shipments from Belgium to the Philippines, the first shipment arriving in 1888. Belgian engineers supervised the assembly of the church, the first column of which was erected on September 11, 1890. The walls were filled with mixed sand, gravel and cement. The stained glass windows were imported from the Henri Oidtmann Company, a German stained glass firm, while local artisans assisted in applying the finishing touches of the steel church.
It has long been reputed that Gustave Eiffel, the French engineer behind the Eiffel Tower and the steel structure within the Statue of Liberty, was involved in the design and construction of San Sebastian Church.
The connection between Eiffel and San Sebastian Church was reportedly confirmed by historian Ambeth Ocampo while doing research in Paris. Ocampo likewise published a report that in the 1970s, the famed architect I. M. Pei had visited Manila to confirm reports he had heard that Eiffel had designed an all-steel church in Asia. When Pei inspected San Sebastian Church, he reportedly pronounced that the metal fixtures and overall structure were indeed designed by Eiffel.
Nonetheless, it is said that the official catalogues of Eiffel make possible reference to the design and exportation of a church in Manila in 1875, or thirteen years before construction of San Sebastian Church actually began. If true, this would still not preclude the possibility that Eiffel had designed the metal structure of the church, with Genaro Palacios completing the actual design of the entire church.