What does a 2-plus-1 road configuration include?

A 2-plus-1 road configuration is characterized by having two non-motorway lanes in one direction and one non-motorway lane in the opposing direction. This type of layout optimizes traffic flow by allowing for overtaking opportunities for vehicles traveling in the direction with two lanes while maintaining a safer and more regulated flow for the opposing direction.

In this design, one lane allows for easier passage, particularly for slower vehicles or when overtaking is necessary, while the single lane on the opposite side helps to manage traffic without the complexity of a dual-lane system in both directions. This configuration is commonly used on rural roads where road safety and efficiency are prioritized. This setup enhances capacity and reduces the likelihood of head-on collisions, which can occur in simpler configurations.

The other configurations mentioned do not capture the essence of the 2-plus-1 road layout and therefore do not apply to its definition. For instance, having multiple lanes in both directions or three lanes all in a single direction does not reflect the intended purpose or traffic management benefits associated with a 2-plus-1 system.