Regulatory Road Sign (R3-4)
No U-Turn Sign Meaning & Driving Rules
The No U-Turn sign (MUTCD R3-4) prohibits drivers from executing a 180-degree turn to travel in the opposite direction at the intersection or roadway opening where posted.
Required Driver Action & Right-of-Way Protocol
Do not make a U-turn. Continue straight or turn onto an approved cross street, roundabout, or parking area to turn around safely.
Detailed Overview & Purpose
The No U-Turn sign utilizes the universal international prohibitory symbol: a bold red circle with a diagonal slash crossing over a curved U-shaped arrow. U-turns are prohibited at locations where limited sight distance, heavy oncoming traffic speeds, or simultaneous right-turning traffic create high collision risks.
Even in the absence of a sign, U-turns are illegal on curves, hill crests where visibility is under 500 feet, in business districts (except at intersections), and on divided highways where no dedicated crossover exists.
Key Standard & Origin: UPS routing algorithms famously avoid U-turns and left turns, reducing vehicle crash exposure by over 30% and saving millions of gallons of fuel annually.
Where You'll Find This Sign
Posted on traffic signal mast arms at busy intersections, freeway median crossovers, and curves with restricted sightlines.
Common Driver Mistakes to Avoid
Making a U-turn from the leftmost turn lane when a No U-Turn sign is clearly mounted on the traffic light mast directly overhead.
How This Sign Appears on the DMV Knowledge & Road Test
High-frequency exam topic covering intersection turn restrictions and general U-turn legality rules.
Legal Penalties and Moving Violations
Illegal U-turns carry moving violation fines ($150–$300), 1 to 2 license points, and fault assignment in turning collisions.
When you encounter the official No U-Turn (R3-4) on a roadway, what is your legal duty?
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