But Concord is not considered a metro area such as San Francisco or Los Angeles. Rather it is part of the San Francisco Bay Area and every city around it is a separate city. So by your qualifications where is the line drawn?
It is urban yes, but in the same way that Inglewood, CA or Yonkers, NY or Skokie, Il is urban. They are part of a bigger metro area, but not the main city of that area. And Concord is not even in the top 5 in population for the Bay Area. So where are the lines drawn? How do your sources figure 615,968?