Road

road, traveled way on which people, animals, or wheeled vehicles move. In modern usage the term road describes a rural, lesser traveled way, while the word street denotes an urban roadway. Highway refers to a major rural traveled way; more recently it has been used for a road, in either a rural or urban area, where points of entrance and exit for traffic are limited and controlled.

The most ancient name for these arteries of travel seems to be the antecedent of the modern way. Way stems from the Middle English wey, which in turn branches from the Latin veho (“I carry”), derived from the Sanskrit vah (“carry,” “go,” or “move”). The word highway goes back to the elevated Roman roads that had a mound or hill formed by earth from the side ditches thrown toward the centre, thus high way. The word street originates with the Latin strata (initially, “paved”) and later strata via (“a way paved with stones”). Street was used by the Anglo-Saxons for all the roads that they inherited from the Romans. By the Middle Ages, constructed roads were to be found only in the towns, and so street took on its modern limited application to town roads. The more recent word road, derived from the Old English word rád (“to ride”) and the Middle English rode or rade (“a mounted journey”), is now used to indicate all vehicular ways.

Modern roads can be classified by type or function. The basic type is the conventional undivided two-way road. Beyond this are divided roads, expressways (divided roads with most side access controlled and some minor at-grade intersections), and freeways (expressways with side access fully controlled and no at-grade intersections). An access-controlled road with direct user charges is known as a tollway. In the United Kingdom freeways and expressways are referred to as motorways.

Functional road types are local streets, which serve only adjacent properties and do not carry through traffic; collector, distributor, and feeder roads, which carry only through traffic from their own area; arterial roads, which carry through traffic from adjacent areas and are the major roads within a region or population centre; and highways, which are the major roads between regions or population centres.

The first half of this article traces the history of roads from earliest times to the present, exploring the factors that have influenced their development and suggesting that in many ways roads have directly reflected the conditions and attitudes of their times. The road is thus one of the oldest continuous and traceable metaphors for civilization and society. The second half of the article explains the factors behind the design, construction, and operation of a modern road. It is shown that a road must interact closely and carefully with the terrain and community through which it passes, with changing vehicle technology, with information technologies, and with the various abilities, deficiencies, and frailties of the individual driver.