When looking at a list of the top 50 most populous cities in the US many more names pop up that haven't been mentioned. Several are sub-cities or suburbs to the major city within the market for instance; Mesa, AZ (in Phx MSA), Fresno, CA (Sacramento MSA), and just outside the top 50; Aurora, CO (Denver MSA) and Stockton, CA (Sacramento MSA again).
Then you have probably one of the most forgotten areas of the country, though a major player in the military and port activity as well as tourism, Virginia Beach, VA. This city is known as the "Hampton Roads" area (Which is comprised of the top 3 cities in VA - VA Beach, Norfolk, and Chesapeake all over 200k residents). I think due to the geographical location being "cut off" from the 95 corridor in VA where all other major cities in the state are and having no competition from NC/MA/and Peninsular VA to its growth. Over 1M people reside in this area but like I mentioned it is often called "Hampton Roads" to refer to the whole coastal area.