Reverse Curve sign

Federal designation W1-4 in the MUTCD, the national standard every state signs to. Common on roads crossing rolling terrain or hugging a riverbank, where the route has to double back through two connected bends in short succession.

How to recognise it

This sign is a diamond stood on its point in yellow, the warning colour. Yellow diamonds telling you what the road is about to do. They are advisory rather than mandatory, but ignoring them is how people end up in ditches and how examiners end up failing you.

What the test wants you to know

Drivers who brake mid curve rather than before it are the ones who lose traction on a reverse curve, because the direction change leaves no straight recovery section between the two bends. Test questions on this sign usually ask when to slow, and the answer is always before you enter, not partway through.

The sign people confuse it with

Reverse Curve gets mixed up with Winding Road more than any other pairing in this category. Put them side by side and the difference is obvious, which is exactly why it is worth doing once rather than meeting them cold in the exam.

Reverse CurveThe road bends one way and then immediately the opposite way, forming an S shape

Winding RoadA series of three or more curves lies ahead, alternating direction over a longer stretch

Practise it

Reading about a sign is not the same as recognising it in half a second with an examiner watching. Every state road signs test on this site shows the sign and asks you to name it, then shows four faces and asks you to pick the right one.

Take a road signs test