How the Romans built roads

Archer B. Hurlbert, in "The Chautauquan," says regarding the cost and methods of building the much quoted Roman roads: "A careful estimate shows that the Romans spent from $30,000 to $100,000 per mile on their roads; yet Europe knew no road building worthy of the name from the fall of Rome, about 400 A. D., to the coming of Napoleon's Tresaguet 1,400 years later.

For a millenium and a half the roads of these men who built for eternity were the best roads in England, Europe and Asia Minor, and though many of them quickly disappeared if neglected, a large number remain to this day, and a much larger number have served as the foundation of modern roads.

One road which Bergier examined in France was raised 20 feet above the surrounding country, and a vertical incision revealed the following sections:
"Sec. 1. A 'fill' of 16 1/2 feet. "
Sec. 2. A foot layer of flat stones and cement. "
Sec. 3. A foot layer of flat stones without cement. "
Sec. 4. A foot layer of firmly packed earth. "
Sec. 5. A half-foot layer of small metal in hard cement. "
Sec. 6. A half-foot layer of large metal and cement. "

The width of Roman roads varied from 120 feet at home to 15 or 20 feet in England. The lesser width made a great reduction in original cost as well as in cost of maintenance. In the case of the narrow roads on the island the work was well done.

The bottom layer, called pavimentum, was one inch thick and made of mortar. This provided a water-resistant base.

 Above the pavimentum were four strata of masonry.

 The layer directly above was called the statumen. It was one foot thick, and was made of stones bound together by cement or clay.

 Above that, there were the rudens, which were made of ten inches of rammed concrete.

The next layer, the nucleus, was made of twelve to eighteen inches of successively laid and rolled layers of concrete.

 A summa crusta of silex or lava polygonal slabs, one to three feet in diameter and eight to twelve inches thick, were laid on top of the rudens.

The crusta was crowned for drainage.

The final upper surface was made of concrete or well smoothed and fitted flint.

https://romanfootprints.com/2012/02/08/ruminating-on-roman-roads/
https://transportationplanninghmm.wordpress.com/2012/06/18/all-roads-lead-to-rome-origins-of-the-highway-system/

We don’t actually know what the Romans called their roads in Britain but the names we do have derive from the Anglo-Saxon and Norse invaders who came after the Romans. Watling Street evolved over the centuries to its present form from the Anglo-Saxon Waclinga straete, meaning road leading to the Waclinga tribe.

 The Stanegate near Hadrian’s Wall comes from stane meaning stone and gate, the Norse for road, so it was known as the stone road.

The laws of the Twelve Tables, dated to approximately 450 BC, specified that roads shall be 8-foot wide where straight, and 16-foot wide where curved.

Viae privatae, rusticae, glareae and agrariae included private or country roads, originally constructed by private individuals, in which their treasure or toil was invested, and who had the power to dedicate them to the public use. Such roads benefited from a “right of way”, in favour either of the public or of the owner of a particular estate.

Viae vicinales comprised roads at or in villages, districts, or crossroads, leading through or towards village. Such roads were considered public or private, according to the fact of their original construction. Such a road, though privately constructed, became a public road when all memory of its private constructors had perished – the Roman equivalent of the 99-year lease enjoyed by 407ETR.

Centurions of the Roman legions generally marched, officers rode horses, and wagons carried their equipment, baggage, and supplies. The formations broke step when crossing bridges, the dangers of harmonic loads on structures having already been recognized.