The Federal Highway Administration [FHWA) identifies functional classification as a key item in transportation data. Streets and highways are grouped into classes according to the service they provide. The California Road System (CRS maps) on this web site display functional classification which is used in determining Federal funding to maintain the roads. To update your jurisdiction, click on Flowchart to Change Functional Classification.
The FHWA stamp of approval is in the lower left corner of each CRS map (PDF), which makes it the official functional classification.
FHWA REVISED Functional ClassificAtion Codes
FHWA has announced the new functional classification codes, which are independent of urban / rural areas. To learn more, see the conversion table below and click on FHWA Memo. To view the FHWA Approved Urban Area, go to Caltrans Earth, then click on the left column Boundaries/Urban Area.
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