Approach Bigwall
As you near the Bigwall, you realize that it is built to straddle a River, by means of a clever arching support scheme that repeats every few feet. The Bigwall follows the River for several hundred feet, terminating at either end in an in-progress rough edge. The end further from you has some Masons working on it. The Road is carrying you directly to a monumental Bigdoor in the Bigtower.
When you heave open the Door and enter, you find a mildly bustling scene. A Bureaucrat is shuffling papers on a serious metal Desk, while Lesser Bureaucrats shuffle papers between slightly less serious metal Desks. You catch glimpses of highly marked-up official Maps, Plans, Forms, and other miscellaneous Paperwork.