Double Curve Sign (Reverse Curve)

The double curve sign, also called the reverse curve sign, is a diamond-shaped yellow warning sign with a black S-shaped arrow showing two curves in opposite directions. The first curve goes one way and the second curve goes the other — forming an S-shape. This sign differs from the winding road sign in that it shows exactly two curves rather than a series of three or more. The arrow indicates which direction the first curve goes (left or right), so you can prepare your steering. When you see this sign, reduce your speed before reaching the first curve. You'll need to steer one direction and then quickly adjust to steer the other direction for the second curve. The transition between curves is particularly challenging because you're changing direction while the vehicle's weight is still shifting from the first curve. This creates a higher risk of losing control, especially in wet conditions or at higher speeds. Double curves often have advisory speed plates below them recommending a safe speed. On mountain roads and winding routes, you may encounter multiple double curve signs in succession. Always complete each set of curves before accelerating.