What does a no-passing zone mean?A no-passing zone is a stretch of road, usually a two-lane bidirectional highway, where you, oncoming traffic, or both are barred from passing the vehicle in front of you. This restriction is usually marked with a solid yellow line appearing on one or both lanes.If there's a solid yellow line on your lane and a broken yellow line on the left lane, it means you can't overtake but oncoming traffic can. If it's reversed (solid yellow line on the left lane side and broken yellow line on yours), you can pass the vehicle in front of you, but oncoming traffic must stay in its lane at all times. If it's a double solid yellow line, no passing can happen on either lane within the entire no-passing zone.In most cases, the pavement markings are enough to indicate the no-passing zone. However, to draw more attention to the zone, officials can decide to install a No Passing Zone sign, also referred to as W14-3. It's a yellow, pennant-shaped road sign with black writing to signify the start of the no-passing zone. You can find it on the left side, and sometimes, it's paired with a white rectangular Do Not Pass sign on the right.Not all roads with solid yellow lines automatically come with the No Passing Zone sign, though. It's optional to have it in some states like Colorado.What should you do when you see a No-Passing Zone sign?Generally, when you're in a no-passing zone, you should be patient, comply with the speed limit, and stay in your lane until the end of the zone. This is especially true if farm equipment or large trucks are in front of you. Never attempt to pass them, as you likely won't see oncoming traffic and might not have enough space in the left lane to overtake.There are, however, some exceptions to the no-passing rule. In many states, the no-passing rule doesn't apply if you're turning left — perhaps from your driveway or into an intersection. In states like Nebraska and Florida, you can overtake in a no-passing zone when there's an obstruction in your lane. Just make sure to do so with care. In Colorado and Minnesota, you can pass in a no-passing zone if it's a bicyclist that's in front of you, and you see no oncoming vehicles. As you do so, set a distance of at least three feet between you and the rider. In Montana, you can overtake a bicycle in a no-passing zone too, but they should be riding at under half of the speed limit in that area, and you won't be overspeeding.If you encounter these exceptions on the road, you can pass on the left as you normally would. First, check for right-of-way vehicles. Once the left lane is clear, switch on your left turn signal light and prepare to move lanes. Then, move right back to the right lane as soon as you're already a couple of feet away from the vehicle you've overtaken. Do this for only one vehicle at a time. If you're the car being passed, slow down a tad bit to let the other driver overtake easier.