road

Roads are engineered conduits that enable movement of people and goods along defined paths. They form the primary element of a road transport network, linking homes, workplaces, markets, and services. A typical road includes a carriageway for vehicles, plus shoulders or verges, drainage, and a right of way that may accommodate sidewalks and crosswalks. The surface, usually asphalt or concrete, sits on stabilized layers that distribute loads.

Roads vary by function and design. Local streets serve neighborhoods; collectors and arterials channel traffic between local roads and higher-capacity facilities; highways and expressways are designed for higher speeds and volumes. In rural areas, gravel or dirt roads may remain common.

Construction and maintenance depend on climate and traffic. Key steps include subgrade preparation, base and surface layers, resurfacing, pothole repair, drainage, and winter maintenance. Road safety relies on speed limits, signage, markings, and lighting, and is supported by standards from national or regional agencies.

Historically, roads originated as simple paths. The Roman road network exemplified early long-distance engineering, while modern roads expanded rapidly with motor vehicles in the 20th century, accompanied by standardized design and funding models.

Environmental and social impacts include land use, emissions, and habitat disruption. Modern practice emphasizes safety, multi-modal options, and sustainable materials and maintenance approaches.