A shoulder (or a hard shoulder) is a reserved area by the verge of a road or motorway. Generally it is kept clear of all traffic. In the event of an emergency or breakdown, a motorist can pull into the hard shoulder to get out of the flow of traffic and obtain an element of safety. A hard shoulder also allows some extra flexibility should a motorist need to take evasive action, as it is a buffer area between the main thoroughfare and the edge of the road. Emergency vehicles such as ambulances and police cars may also use the shoulder to bypass traffic congestion. These uses lead to the alternative names breakdown lane and emergency lane.
In some parts of the world, standing on the shoulder of a motorway is forbidden. A list of countries where it is allowed can be found in the article highway. If it is a shoulder where it is legal to stand on, it can be a good spot to hitch a ride. These places can often be found along on-ramps.
Hard shoulder along an on-ramp in Germany
Hard shoulder along an on-ramp in the Netherlands
Shoulder along a road in Bulgaria