Which of the following best describes the purpose of a crawler lane?

• A. To enable emergency vehicles to reach the scene quickly
• B. To allow other traffic to overtake on the nearside
• C. To allow slow-moving traffic to move further left on uphill gradients
• D. To permit large vehicles to park out of the way

Answer: (C)

A crawler lane is an extra lane on uphill gradients that is used by slow-moving vehicles, especially heavy goods vehicles, so they can keep to the left and “crawl” without blocking the rest of the traffic. This helps the faster vehicles have space to overtake on the remaining lanes to the right, keeping the traffic flow smoother and reducing congestion on climbs. It’s not for emergency vehicles to reach a scene faster, it isn’t about overtaking on the nearside (left), and it isn’t intended for parking large vehicles out of the way.