What does the fishbone line on the highway mean?
3 Answers
Fishbone lines on highways often appear near tunnels, with the main purpose of reminding drivers to slow down. These fishbone lines have solid or dashed lines in the middle, and the spacing is not fixed - it gradually widens from narrow to wide. Initially, the spacing may be only about 10 cm, but as vehicles approach, the fishbone lines gradually become wider. Highways have many markings and signs, each representing different meanings and used in different locations to provide various warnings and instructions to passing drivers. A highway is a multi-lane road exclusively designed for directional and lane-based vehicle traffic, with full access control. The annual average daily traffic volume on highways should ideally exceed 15,000 passenger cars, with design speeds ranging from 80 to 120 kilometers per hour.
The fishbone markings on highways are actually a type of deceleration marking, designed to resemble fishbones, with short and dense lines arranged in parallel along the lane edges or in the center. Having driven long distances for many years, I often see them near highway exits, toll booths, or sharp curves. They primarily work by providing visual cues and a slight vibration to instinctively prompt drivers to slow down. If you drive over them at high speed, the car will shake a bit, effectively preventing fatigue-related driving or speeding hazards. Once during a night drive, they woke me up, and later I researched and found that this design also helps reduce accident rates. In short, it’s not just a traffic safety measure but also an engineering marvel, helping everyone travel smoothly.
When I saw the fishbone lines, I thought they were just patterns to narrow the road. As a new driver who just got my license, I learned in the highway course: they're called deceleration guide lines, designed to force you to slow down, preventing collisions at congested entrances or loss of control on curves. I've tried it myself a few times—when speed exceeds 50 km/h, you'll feel bumps, which serve as a practical reminder. Experts say they're also paired with yellow and white lines to enhance visibility, especially important at night. My advice to new drivers is not to panic when encountering them—just slow down properly, as safety comes first.
