IELTS Academic Reading Practice Test 19: Passage 1

In 312 BC, the Roman official Appius Claudius Caecus ordered the construction of a road running south-east from Rome to the city of Capua, some 200 kilometres away. The Via Appia, which was later extended to the port of Brundisium on the Adriatic coast, was the first of the great Roman highways, and many others soon followed. By the time the empire reached its greatest size in the second century AD, a network of paved roads tens of thousands of kilometres long linked Rome with its provinces, from northern Britain to the Middle East. Although the roads came to carry merchants, travellers and goods, their original purpose was military: they allowed legions to march quickly, in any season, to wherever they were needed.

Before any digging began, the route had to be planned by surveyors. Their main instrument was the groma, a vertical staff with a horizontal cross at the top, from each arm of which hung a weighted cord. By looking along two opposite cords, a surveyor could line up distant poles and so lay out a straight line across the landscape. To check that the ground was level, surveyors used a device called a chorobates, a wooden table about six metres long with a channel for water along its top. Roman roads are famous for their straightness, but they were not built straight at any cost. In hilly country, engineers frequently changed direction to keep the slope gentle enough for loaded carts and pack animals, and roads often zigzagged up steep hillsides.

Many modern books describe the road itself as consisting of four distinct layers, each with a Latin name. This tidy account, however, is largely based on instructions written by the architect Vitruvius in the first century BC, which were in fact intended for laying floors rather than roads, and archaeologists have found that Roman roads varied considerably, depending on local materials and the importance of the route. Nevertheless, the best-built roads did follow a broadly similar pattern.

Seen in cross-section, a well-built road was surprisingly deep. On the most important routes, especially near towns, the surface consisted of large, close-fitting blocks of basalt, a hard volcanic rock, cut into irregular many-sided shapes; such surfaces could last for centuries. Beneath the paving lay the nucleus, a fine layer of gravel, sand or crushed tile mixed with lime and pressed down firmly. Below this was the rudus, a thicker layer of smaller stones held together with lime mortar, and under that the statumen, a layer of large, flat stones that formed the road's foundation. All of this rested on the floor of a trench, sometimes a metre or more deep, which the builders had dug down to firm subsoil and then levelled and beaten hard. In the provinces, however, many roads were simply surfaced with gravel, which was cheaper to lay and easier to repair.

Water was the greatest enemy of any road, and Roman engineers went to considerable trouble to keep it out. Many roads were built on an agger, a raised bank of earth and stones that could be more than a metre high, which kept the road above flood level and helped it to drain. The surface was given a slight camber, higher in the middle than at the edges, so that rainwater ran off into ditches dug along both sides, while kerbstones held the edges of the surface in place. Rivers were crossed by stone bridges, some of which are still in use today.

Much of the work, especially in the provinces, was done by soldiers, who were expected to build roads as well as fight, although civilian labourers and sometimes slaves were also employed. Once a road was complete, milestones were placed at every Roman mile, a distance of a thousand paces, showing the distance to the nearest town or to Rome itself. Along the main routes, the state also maintained a chain of stations for the cursus publicus, the official courier service, where messengers could change horses and officials could find food and a bed for the night. Using this system, an urgent message could sometimes cover well over a hundred kilometres in a single day.

Many Roman roads remained in use long after the western half of the empire collapsed in the fifth century. Without a central authority to maintain them, however, they slowly decayed. Later communities often removed the paving stones to use in their own buildings, and many routes gradually disappeared beneath fields and forests. Yet the lines that Roman surveyors drew across Europe have proved remarkably lasting. In Britain, several modern main roads still follow Roman routes for long distances, and in Italy stretches of the Via Appia itself can still be walked, their ancient paving stones worn smooth by more than two thousand years of traffic.