Roman roads, ancient system of highways linking Rome with its provinces. Their primary purpose was military, but they also were of great commercial importance and brought the distant provinces in touch with the capital. The roads often ran in a straight line, regardless of obstacles, and were efficiently constructed, generally in four layers of materials; the uppermost layer was a pavement of flat, hard stones, concrete, or pebbles set in mortar. Roads were built or rebuilt by the Romans throughout the empire in Europe, Asia, and Africa. Many modern roads are laid out on their routes, and some of the old bridges are still in use. Examples of Roman roads exist near Rome and elsewhere.

In Italy roads led out of Rome in every direction. The most ancient were the Ostiense Road to Ostia at the mouth of the Tiber; the Praenestine Way SE to Praeneste; and the Latin Road or Latin Way to a point near Capua where it later joined the Appian Way, which was the first of the great highways. The Flaminian Way was the most important northern route. It ran from Rome NE to Ariminium (Rimini); from that point it was extended (187 BC) as the Aemilian Way, which ran in a straight line NW through Bononia (modern Bologna) to the Po at Placentia (Piacenza); later it was extended farther to Mediolanum (Milan). Another northern route was the Aurelian Way from Rome along the Tyrrhenian coast to Pisae (Pisa) and Luna; from there it was extended to Genua (Genoa). The third northern route was the Cassian Way from Rome through Etruria to Faesulae (Fiesole) and Luca (Lucca); near Luca it joined the Aurelian Way. The three roads from Rome to the north were connected with others crossing the Alps by the great Alpine passes—Alpis Cottia (Montgenèvre), Alpis Graia (Little St. Bernard), Alpis Poenina (Great St. Bernard), the Brenner Pass, and others leading into Rhaetia and Noricum.

The chief roads leading from Rome to the regions across the Apennines and to the Adriatic were the Salarian Way to Ancona and the Valerian Way to Aternum (Pescara). There were other roads in Italy, most notable among them the Postumian Way, leading from Genua across the Po valley to Aquileia at the head of the Adriatic. A wide system of roads was also built and rebuilt by the Romans in Britain, mainly for military purposes. The best-known British roads were Ermine Street, Fosse Way, Watling Street, and the pre-Roman Icknield Street.

See T. Ashby, The Roman Campagna in Classical Times (1927, repr. 1970); I. D. Margary, Roman Roads in Britain (2 vol., 1955–57; rev. ed. 1967); V. W. Von Hagen, The Roads that Led to Rome (1967).