Plainfield is a city in Union County, New Jersey.
To the northwest is North Plainfield, a borough in Somerset County.
To the south is South Plainfield, a borough in Middlesex County.
Below is a map of these boundaries.
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| Map showing shared boundaries of North Plainfield, Plainfield, and South Plainfield. New Jersey Department of Transportation |
Below is a map of the wider area within New Jersey.
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| Map showing area of New Jersey containing the three Plainfields. Map of New Jersey Department of Transportation |
Accuracy is important in genealogy. The location of an event or residence is where we would begin looking for records. The counties recorded marriages until the later 1800s, when state filing took over. The counties still process and maintain probate records.
I just realized this tricky naming pattern spread across three counties and thought I'd share with fellow New Jersey researchers.

