Port Alexander is a thriving (sort of) metropolis on the east coast of the UCAS, near the border with the CAS. As is typical, there are corporations and arcologies dotting the landscape, and blight between them. There is also the best space-port in the UCAS, and possibly in North America. Lots of sub-orbital and LEO traffic goes through here, and UCAS takes a cut.
Sometimes so do other people ...
Old Town is still the home of the richest and most powerful people in Port Alexander. Compounds for corporate executives, powerful criminals and the like are the norm here.
Midtown is home to most of the arcologies, as well as the various malls, arcades and so forth that cater to the better off - and legal - citizens of Port Alexander.
Commerce City is almost entirely slums now, where once industry rules. The Ramparts ("The 'Parts") is particularly notorious.