carriageway

A carriageway is the part of a road that is designated for vehicular traffic. It is the surfaced area bounded by road edges, kerbs, verges, or other boundaries and is distinct from ancillary elements such as footways and cycle tracks. The term is commonly used in British English and civil engineering to refer to the traveled way of a road.

Carriageways can be configured in different ways. A single carriageway carries traffic in one direction, while a dual or multi-carriageway has two or more lanes for traffic in the same direction. When opposite-direction carriageways are present, they are typically separated by a central reservation or barrier, forming a dual carriageway. On motorways and some high-capacity roads, each direction often has its own carriageway with limited access and physical separation.

Key design and features include lane markings, edge lines, and, where present, hard shoulders or emergency lanes. The surface is usually asphalt or concrete, and lane widths vary by country and road class but commonly fall around three meters per lane. Carriageways are designed to support efficient traffic flow and safety, with design standards governing capacity, sight distance, and resilience to weather and wear.

In usage, carriageway describes the part of the road allocated to vehicle movement, distinct from pedestrian areas or cycling routes. The term is widely used in Commonwealth countries; in some regions, “roadway” or simply “road” may be used in similar contexts.