Some genealogical software draws on the API for Google Maps so the user can plot the events on a map. This might be a desktop-based application such as Calico Pie's Family Historian, or a web-based one, such as MyHeritage's new Pedigree Map. Or it could be a general-purpose GIS program which the user has pressed into service for family history purposes.

To take advantage of mapping features, and other features in the software, users may standardize the place names in their genealogy database to the modern name for a place, rather like the Family History Library or other repositories might choose a specific gazetteer for their place authority -- only in this case, the standard place authority is the current map you see when you use Google Earth, or whatever place authority the GIS system uses.

However, some modern metropolitan areas extend past the borders of counties, and sometimes sprawl over state lines. If a town crosses county boundaries, how do you make the decision about which county to standardize on?

I would like to know:

  • What are the criteria you use to make your decision?
  • Which geographical reference works or tools have been helpful to you?
  • How do you remember to check records in all the relevant jurisdictions?
  • What are the advantages and disadvantages of using your approach to the problem?

(I'm restricting this question to the US so that we can develop questions and answers for different countries.)

Records generated by a particular county will have a specific county on them. Records which have a specific street address will reveal which county the residence is in, or where the event took place. However some items, such as newspaper obituaries, will simply refer to someone being a resident of, or simply "of" the town name. I am assuming that the researcher is recording in notes exactly what appears on the documents.

  • 2
    This List of U.S. municipalities in multiple counties shows there are many municipalities that might place you in this predicament!
    – Harry V.
    Commented Nov 6, 2016 at 22:04
  • My gut reaction would be that if knowing the county is important (most of my research is focused in New England, so the county is basically irrelevant for most things), then you would want to indicate the county where the event actually took place. If you don't know that information or it isn't terribly important, I would list the county where the historic center of town/original settlement was located.
    – Jack
    Commented Feb 24, 2019 at 0:49

4 Answers 4


Your last paragraph about records just about answered your own question.

As you say, county records and records with street addresses give you the county.

Therefore, if you only have records that give you the town name for a person, then check the county records for each possible county for that person, or look in other records for a street address for that person in that town.

If the record is from over 50 years ago, most cities were much smaller. See if you can find a map from the time, and locate what modern county it would have been in.

Yes, metropolitan areas often cross county boundaries. But the city proper usually doesn't. With no other information, I'd use the county of the city proper, and if that still crosses boundaries, then I'd use the county that the center of the city is in.


Having commented, I probably should put my money where my mouth is and describe my solution - unfortunately for general applicability, as a UK based genealogist, I have only noticed one such place in my data, which is New York City. That's not to say that there aren't others that I haven't noticed. But for the sake of completeness....

While my normal format for an American place is settlement, county, state, USA, I make an exception for New York. In my data, GG Aunt Augusta lived in "Manhattan, New York City, New York State, USA". Effectively, the county is omitted and the City floats up to occupy the county slot. This only really works because people don't need the county to qualify where NYC is. (I further confess to doing the same with London, England). Note that floating place names up into unusual positions does require the explicit statement of what type of place this is, if there is any duplication or doubt.

Having looked at the link for places crossing boundaries, I suspect that there aren't many such places where omission of the county wouldn't result in information loss.

  • New York City is a special case, because of the consolidation of the five boroughs. Manhattan = New York County. If you have "NY City" and nothing else, post-consolidation, you don't know the county.
    – Jan Murphy
    Commented Nov 15, 2016 at 18:20
  • Yes. Fortunately the records say Manhattan in most cases. I suspect that if I needed to explicitly state the County (rather than the Borough), then careful naming of the source would work. And if I remember, at least one of those Boros for at least some time, was only part of the County.
    – AdrianB38
    Commented Nov 15, 2016 at 18:47
  • 1
    That answer was a hostage to fortune. Augusta lived in Kansas City, MO before moving to NYC. The link shows KC to be a cross county city as well. The census has her in KC, Jackson Co so I realise that I have simply assumed all her KC references were Jackson Co. Oh dear. And now I'm worried that she might even have lived in Kansas City, Kansas state. More checking needed.
    – AdrianB38
    Commented Nov 15, 2016 at 18:57
  • That's probably one of the most famous cases in the US. When baseball fans mocked one of my favorite players with signs, one read "Hunter Pence thinks Kansas City is in Kansas." Google "Hunter Pence signs" if you want to know more.
    – Jan Murphy
    Commented Nov 15, 2016 at 19:07
  • 1
    Relief. Having assembled some maps, I went through Augusta's known addresses and found them (or what was left of them) in Streetview. All are well within Jackson Co when compared to the other 3 MO counties. She did get within 2 blocks of the State boundary with Kansas on one occasion. As a learning point, it was not easy to find maps that combined counties with streets / settlements. E.g. Her employer seems to reside now in a cemetery straddling the border btw KC and Independence. Can't be sure. Best is lib.utexas.edu/maps/historical/kansas_city_1907.jpg combined with Streetview
    – AdrianB38
    Commented Nov 15, 2016 at 22:16

Since I now live and work in England I do not know all that much about modern American records. Given that I also very rarely work on records which are less than a hundred years old and are far more like to be two, three or four hundred years old. That being said I do however have a detailed background in researching English families in the British Isles and or English or English Colonial families in many parts of the world.

It is however clear that for the earlier period both the records system, the records and legal system are directly derived from that of the English system and the English Common Law and the English Ecclesiastical. Therefore in order to extend back any given family line. The researcher would sooner or later have to work from Parish records in order to trace the family and or to extend back the family line. In order to do so successfully the researcher would require at least a basic understanding of the legal system at the period in question. The Parish system and that of the Parish boundaries for the required area and such things as the differences between Civil Parishes and Ecclesiastical Parishes and the resultant effect or otherwise of these and boundaries and jurisdictions and the significance of these sources upon the records that they are researching in order to trace the required family. If the records covered are not correctly brought back and full grounded upon the parish system. The family and the family line traced may or may not be the correct family as the family and family line as required by the researcher.


It sounds as though the question is: when a city crosses county lines, which county should one choose as for the "standard" place name for that city? If so, I think (and as @Ikessler implies), you probably shouldn't, for the reasons already given, but rather use the county with the corresponding record repository.

Possibly the most extreme example is New York City, each borough of which is a distinct county. As it happens, New York County is the borough of Manhatten, so "New York, New York, USA" may actually be correct in many cases.

I've used Wikipedia as a gazetteer, as it's generally pretty good about indicating when a given locate straddles county boundaries (in some cases more than two). Bryn Mawr, Pennsylvania, is an example of a locale that spans three townships in two counties. From the Wikipedia info, you can generally determine where to look for recent records (historical records, of course, depend on how the county boundaries have changed over the years, and that information is usually also included in the Wikipedia articles).

  • I can't help but dislike "New York, New York, USA". Is that New York State? New York County? New York City? And ask the question twice. I am troubled by the tendency of American genealogists to not use qualifiers such as "Co.".
    – AdrianB38
    Commented Nov 14, 2016 at 19:17
  • Agreed, especially given the number of places where a given place name could be either a county or a town (possibly a town in a different county). "New York, New York, USA" doesn't bother me so much (it's at least accurate, if not precise), but does e.g., "Somerset, New Jersey" refer to Somerset County? Or the town of Somerset in Mercer County? I also must say that I hadn't noticed this lack of accuracy/precision to be specific to American genealogists. Do you perhaps have data to support that characterization?
    – cleaverkin
    Commented Dec 4, 2016 at 22:00
  • The FamilySearch standard location list is one that omits "Co." - I think Ancestry's drop down lists do likewise. So I'm taking those as symptomatic of US genealogy in general. Now UK genealogists don't add "Co." either, but we don't need to as the names are normally unique - we have no town called Cornwall, say. Where there is potential duplication, then the county name is prefixed by "County", eg "County Durham". Indeed that formula appears to be followed for all Irish counties regardless of duplication. So entirely accidentally UK genealogy doesn't seem to have a county name problem.
    – AdrianB38
    Commented Dec 4, 2016 at 22:14
  • So I can't claim any great virtue for UK genealogists. It just happens not to be an issue. Ireland is virtuous with its county names.
    – AdrianB38
    Commented Dec 4, 2016 at 22:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.