You are on, or being directed to, a numbered interstate. Even numbers run east-west, odd numbers north-south; three-digit numbers are loops and spurs around cities.
Use the number and direction plaque to confirm your route. Navigation is the one job of every guide sign: they inform, they never command.
Even = east-west, odd = north-south. I-10 crosses the country; I-5 climbs it.
Confusing route guidance with rules. Guide signs never require anything; if a maneuver is needed for your exit, plan lanes early.
Signs that live in the same family, or get confused with this one.
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