Does copyright protect architecture?

Yes, but only for designs after 1990 and not for photos of the building itself..

“Architectural works became subject to copyright protection on December 1, 1990. The copyright law defines “architectural work” as “the design of a building embodied in any tangible medium of expression, including a building, architectural plans, or drawings.” Copyright protection extends to any architectural work created on or after December 1, 1990. Architectural designs embodied in buildings constructed prior to December 1, 1990, are not eligible for copyright protection.”
— U.S. Copyright Office