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FHWA Functional Classification Guidelines


Note: This publication was updated in 2013. This version is for archival purposes. For the current version, see

Revised in 1989, this document was electronically scanned in April, 2000. The scanned image wa s processed through Optical Character Recognition software, the resulting text being formatted for the World Wide Web. Changes are restricted to:

Original page numbers are retained, providing easy reference back to the original document in hardcopy form. They also provide a convenient location on the page from which to link to another electronic page.

Section Links to electronic pages Original Hard Copy Page #
I Introduction I-1
II Concepts, Definitions, and System Characteristics II-1
The Concept of Functional Classification II-1
Area Definitions II-5
Functional System Characteristics II-8
Functional systems for rural areas II-8
Functional systems in urbanized areas II-11
Functional systems for small urban areas II-14
Special urban-rural identification II-15
Classification criteria for Alaska, Hawaii and Puerto Rico II-15
III Suggested Procedures for Rural, Small Urban Aarea and Urbanized Area Classification III-1
Introduction III-1
Classification Procedures for Rural Systems III-3
Identifying and ranking population centers and other travel generators III-3
Classification of rural systems III-6
Classification Procedures for Small Urban Areas III-14
Determine and map the urban area boundary III-15
Prepare road network map III-15
Identify and map land service characteristics III-15
Classify the highway and street network III-15
Classification Procedures for Urbanized Areas III-18
Determine and map the urbanized area boundary III-18
Map the road network III-19
Perform preliminary classification of the total arterial system III-19
Classify the final arterial system III-28
Classify the principal and minor arterial street systems III-28
Substratify the principal arterial system III-32
Classify collector and local streets III-34
Attachment 3 - Addendum  
Updated: 10/7/2013
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