Regional Codes ...
For statistical purposes, the US Census Bureau has divided the country into four Regions. Duvall is located in Region #3 (the South Region).
In turn, the US Census Bureau has further divided each Region into Divisions. Duvall is located in Division #6 (the East South-Central Division).
The Office of Management and Budget (OMB) has created ten Federal Regions. Duvall is located in Region IV (Region 4).
Referenced GNIS Records ...
GNIS ID #117703 (Name of Record: Duvall)
Class: populated place
A place or area having clustered or scattered buildings and a permanent population (such as a city, settlement, town or village). The boundaries may or may not coincide with the perceived population.
A 'populated place' record may have a corresponding 'census' or 'civil' record. The information contained in the 'populated place' record applies only to the class and should not be confused with either the 'census' and 'civil' classes.
Map Name: Opp East
Lat: 31.2762797 Lon: -86.2418949 [Map]
Elev: 101 ft.
Referenced FIPS Records ...
FIPS Code: 01/21976 (Place Name: Duvall)
County: Covington (FIPS State/County: 01/039)
Identifies a populated place (ie- Duvall) which is wholly or substantially located within the boundaries of an incorporated place with a different name. The Part of Code identifies the incorporated place.