You’re driving along a motorway and see this sign. What does it mean?

Explanation: Where a motorway has a long or steep gradient, slow-moving large vehicles might get in the way of other traffic. To help the traffic flow, an extra lane - called a crawler lane - is sometimes found on these gradients. This helps the traffic to flow by providing the slower heavy vehicles with a dedicated lane on the left.

Category: The Road

References: The Official DVSA Guide to Driving Buses and Coaches: Section 4, The Official DVSA Guide to Driving Goods Vehicles: Section 4