Some locations have precise geographic borders. Those borders may change over time, but often are reasonably well-established. Some places, particularly those whose names are informal and known to locals, may have more fluid boundaries or just be a general area. Ethnic regions of some urban areas can change over time and have boundaries that are in a constant state of flux or have no precise definition. In some rural areas, certain areas may have a name that known to locals but does not appear on any map, post office list, or other geographic finding aid.
Frequently these items are mentioned in newspapers, family letters and correspondence, and other unofficial records. Some thoughts on locating such places can be found in our recent post on Prairie Precinct in Winnebago County, Illinois.