Carriageway

A carriageway (British English)[1] or roadway (North American English)[2] consists of a width of road on which a vehicle is not restricted by any physical barriers or separation to move laterally.A single carriageway road (North American English: undivided highway) has one carriageway with 1, 2 or more lanes together with any associated footways (North American English: sidewalk) and road verges (North American English: tree belt, parkway, or other regional variants).A dual carriageway road (North American English: divided highway) has two roadways separated by a central reservation (North American English: median)."Cars only" lanes may be physically separated from those open to mixed traffic including trucks and buses.Some cities such as Pittsburgh, Pennsylvania, have many bus-only roadways to alleviate congestion related to public transit buses, despite its very challenging topography which severely limits the extent to which arterial roadways can be added or augmented.
Diagram showing different arrangements of the elements of a road
An intersection of the German A7 Autobahn near Hamburg showing slip roads as well as shoulders
Roadway (disambiguation)GermanAutobahnHamburgslip roadsshouldersBritish EnglishNorth American Englishtraffic lanesshoulderofframpsingle carriagewayfootwaysroad vergesdual carriagewaycentral reservationlocal-expressNew Jersey TurnpikePennsylvania TurnpikeGeorge Washington BridgeFort LeeHigh-occupancy vehicle lanesPittsburgh, PennsylvaniaChausseeFrontage road / laneGeometric design of roads