OK, three guesses: what is this building?

It’s not a factory.
It’s not a warehouse.
Not a school.
And no, not an office building either.
It’s a close-up look of the structures immediately above the back entrance of First Baptist Church of San Antonio, where I went to church this morning. It’s an immense conglomeration of buildings that goes back to 1864 or so, according to an usher that I spoke too.
One piece was added on by building right over a city street. That’s what this passageway used to be … this shot shows what used to be the exterior of Webb Hall:
