The round yellow sign with a black X and the letters R R is the advance warning for a railroad crossing. It is one of only two shapes reserved for a single meaning, the circle for rail crossings and the pentagon for school areas, so it is recognizable long before the legend is readable.
It is posted well before the tracks, placed to give you time to slow, look, and settle traffic behind you before the crossbuck at the rails. Between the round sign and the crossing you may also find pavement markings, an X with R R painted in the lane.
Slow down, look and listen for a train, and be prepared to stop at the crossing ahead. Check your mirror so a following driver is not surprised by your braking. Never race the distance to beat a train you can already see; judge nothing about a train's speed except that it is faster than it looks.
The classic exam pair is this sign versus the crossbuck: the round yellow sign warns in advance, the white X-shaped crossbuck stands at the tracks and legally works as a yield. Questions about shape alone also use it, since the circle means railroad warning and nothing else.
This sign appears in 25 questions across 25 of our state banks, on Driver License practice tests. Start with your state:
A circular yellow warning sign appears ahead. Which hazard does the manual's shape chart associate with it?
Why: The manual's sign-shape chart assigns a circular sign to an advance railroad warning. Therefore, the proposed response is "A railroad crossing ahead".
Every practice test explains its answers this way. Pick your state and take one free; no sign-up.
Choose your stateA railroad crossing is ahead. It is the advance warning, posted before the tracks so you have time to slow down, look and listen, and be ready to stop at the crossbuck.
The round yellow sign warns before the crossing; the white X-shaped crossbuck marks the crossing itself and acts as a yield sign for trains. One prepares you, the other is the decision point.
The circle is reserved for railroad advance warning, so the shape alone identifies it at distance or when the face is obscured. Written tests ask for the meaning of the shape for exactly that reason.
Reduce speed, look both ways along the rail line, listen, and check your mirrors. Plan to stop if a train is approaching, and never queue onto the tracks in slow traffic.
Yes. Many approaches paint a large X with R R in the lane before the crossing. Marking and sign carry the same message: the crossing is close, slow down now.