This is the central entryway of the Kunsthistorisches Museum in Vienna.
The building was built by Emperor Franz Joseph I of Austria-Hungary between 1872 and 1891 in order to bring together and display the Habsburgs' formidable art collection.
To give you an idea of the scale of this building, note the opening in the lower right of the rightmost door which is a standard opening of approx. 6.6 feet high.
I've added two close-ups of the doorway to the workshop to show some of the detail.