You haven't toldd us much about what usuallly happens to "urban studies" majors after graduation, but assuming you add advanced degrees in related, and possibly-more-marketable fields after graduation, I'd suggest transportation studies (often called "physiical distribution", "business logistics" or ""supply chain management").
And if you're geared toward the academic life, I'd definitely look into advanced courses in transportation economics. This is a field that's likely to get more attention as the pressures of a dwindling supply of fossil fuel forces us to redesign our entire transportation system. It's not one that either the public or the journalistic profession grasp easily, however, so it might find itself in greater demand someday.
What a revoltin' development this is! (William Bendix)