Anywhere?
A commonly held misconception is that as an undergrad, you have to go somewhere “known” or “highly-ranked” for your specific major. Even setting aside the fact that college students frequently change their major, that’s simply untrue. You just need to go to an overall good university with a solid department/major in your field, particularly when your major is something like sociology which is offered virtually everywhere. For example, note that the excellent liberal arts colleges like Amherst, Swarthmore, Reed, Pomona, etc., aren’t going to be represented in departmental rankings because those are based on doctoral programs and research dollars. But they may be excellent places to start a career.
Still, some research universities with excellent sociology departments that otherwise more or less fit your criteria are Harvard, Princeton, Penn, UMiami, Stanford, Columbia, Brown, Northwestern, Syracuse, NYU, Case Western, Emory, Northeastern, Brandeis, Boston College, Fordham, Howard, and Boston University. Duke and Vanderbilt also have great departments but those are going to have a strong Greek life. Brown and Cornell also have strong departments, but they’re both in cold weather and Cornell is rather rural.
But don’t discount good overall colleges/universities with mid-sized populations that aren’t on this list. For example, Georgetown isn’t ranked because they simply don’t have a doctoral program in sociology, but they have a truly excellent faculty doing great research and coming from the top departments in sociology. In fact, mid-sized universities in urban areas often have better faculties than you’d otherwise expect in part because they are located in desirable areas; professors who would normally want to work at higher-tier schools often work there because they want to live in that city or want to give their spouses/partners job opportunities. American University also is not ranked because it doesn’t have a PhD program in sociology, and it’s not necessarily the most elite university (excellent university! Just not super-elite). But it seems to have a truly excellent sociology department - the professors come from top doctoral programs and are heavily involved in research in their fields. (In fact, I recognized the names of two of the professors, one of whom is very active in my former field of HIV research. She publishes a LOT.)
So my advice to you is to scope out universities that are overall appealing to you in urban and suburban areas and then check out their sociology departments, not the other way around. Make sure you are taking into account other areas of the quality of education and overall experience, too. You’ll only take about 1/3 of your classes in the sociology department; so much of your experience will be shaped by your classmates, the location, the atmosphere, extracurricular activities, internships, etc.