Comment by dredmorbius
Comment by dredmorbius 5 days ago
FWIW, Wikipedia has a list of the most common place names in the United States. "Washington" leads at 91, which means nearly two occurrences per state, though this includes variant names such as "Old Washington", "Port Washington", and "Washingtonville":
<https://en.wikipedia.org/wiki/List_of_the_most_common_U.S._p...>
Other issues you might want to consider are locations with multiple names or spelling variants, say, "Ciudad de México" and "Mexico City" or Pretoria/Tshwane, various script variants, or disputed names. Or closely-paired locations, such as Minneapolis / St. Paul or Dallas / Fort Worth. Or those which have changed names (Bombay / Mumbai, Calcutta / Kolkota, Madras / Chennai).
For the United States, using MSA (Metropolitan Statistical Area) will tend to group people by urban region, with less ambiguity and grouping of reasonably proximate locations. Unfortunately there doesn't seem to be a widely-used standard elsewhere.
Cue: "Falsehoods programmers believe about geography"