Narrow bridge sign
A yellow diamond with two lines that pinch in. It warns of a bridge ahead that is narrower than the road leading to it.
Rules vary by state and country. This explains the sign's standard meaning in the U.S. Manual on Uniform Traffic Control Devices; it isn't legal advice.
How to read it
The MUTCD uses it ahead of a bridge or culvert 16 to 18 feet wide between its sides, or narrower than the lanes that lead to it, and may also use it where the shoulders narrow or disappear on the approach. Pennsylvania's manual adds that such a bridge generally has no shoulder.
Narrow or one lane
A narrow bridge still carries two lanes, as Florida's handbook puts it, with very little clearance. A bridge less than 16 feet wide gets a different sign, ONE LANE BRIDGE: only one vehicle fits at a time.
More road signs
Sources
- MUTCD 2009 Edition, Chapter 2C: Warning Signs and Object Markers, MUTCD 2009, Part 2, U.S. Federal Highway Administration, Sections 2C.20–2C.21
- Pennsylvania Driver's Manual, Chapter 2: Signals, Signs and Pavement Markings, Pennsylvania Department of Transportation, p. 15
- Official Florida Driver License Handbook, rev. 08/2023, Florida Department of Highway Safety and Motor Vehicles, p. 51
Last reviewed September 25, 2026 by Rory Hansen. How we research