assign different cities in the same "metropolitan area" into a group/list

Background/research:
I understand locations work via city, region, country. I do not see a way to allow for metropolitan area (example – multiple, different cities in the same area).

My question is, how can I assign different cities in the same “area” into a group/list. Example – Atlanta, GA. I have listings cities throughout the Atlanta area, including Atlanta GA, Woodstock GA, Alpharetta GA, Johns Creek GA.

My End goal is to be able to create pages such as “Best Local Elderberry Syrup in Atlanta”

When I search in Atlanta, I only get the Syrup in Atlanta (city).
https://findelderberry.com/search/?geodir_search=1&stype=gd_place&s=+&snear=&sgeo_lat=&sgeo_lon=&city=atlanta

Here you can see all of the syrups in my database, which is the Atlanta area only at the moment.
https://findelderberry.com/local-syrups/