Interstates: Interstate nn (I-nn) State: State Route nn (SR-nn) | US Highways: U.S. Route nn (US-nn) | |
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The State Route System in Alabama uses the standard numbering convention: odd numbers signify a north-south state route, and even numbers signify an east-west route. Often more than one route number shares the same roadway, so identifying which route the mile markers are for is often difficult.
In no case does a state route number mirror a U.S. Highway number. As such, the following state routes do not exist: 11, 29, 31, 43, 45, 72, 78, 80, 82, 84, 90, 98, 231, 278, 280, 331, 411, or 431.
Current State Routes
Lengths are from ADOT Milepost Maps unless otherwise noted
References
List of state routes in Alabama Wikipedia(Text) CC BY-SA