The saying goes ‘All roads lead to Rome’ – but a new study suggests these paths weren’t as uniformly straight as once thought.

Researchers have analysed 186,000 miles (300,000km) of Roman roads across the former empire, creating the most detailed picture yet of how the network was structured.

It has long been thought that Rome lay in the centre of this web, and that Romans tended to build straight, paved roads.

However, they discovered a complex network that was shaped by the local geography and steepness of the surrounding areas.

What’s more, other cities such as Ankara and Byzantium, both in Turkey, were more centrally located within the road network than Rome itself.

‘The study shows that Roman engineers adapted road construction to the landscape,’ lead author Dr Adam Pazout, from Universitat Autònoma de Barcelona, said.

‘While they favoured straight routes where possible, the roads were generally less straight than major modern ones.

‘Mountains, valleys, rivers and settlements all helped shape their routes, while engineering techniques such as terracing, rock cutting, retaining walls and bridges allowed roads to cross challenging terrain.’

Called Itiner–e, the incredible map captures a stunning snapshot of the Roman Empire’s vast transportation system as it was nearly 2,000 years ago 

Pictured, Roman roads snaking through mountain passes leading to Delphi in ancient Greece. The complex network was shaped by local geography, experts said

For the study, the researchers studied the structural characteristics of Roman roads using a digital model they previously created.

Called Itiner–e, the incredible map captures a stunning snapshot of the Roman Empire’s vast transportation system as it was nearly 2,000 years ago.

It stretched a whopping 1.5 million sq miles across Europe, from northern England to France, Spain, Greece and Turkey right down into northern parts of Africa.

Along these highways, Romans transported people, military equipment, food, wine and much more in chariots and carriages of wood pulled by horses.

The researchers analysed four key properties of the local landscape – average and maximum slope, elevation, orientation and road ‘straightness’.

These were then compared with modern paved roads across the same area.

Analysis revealed Roman roads were predominantly straight where the landscape permitted.

However, in hillier areas they tended to be less straight than modern roads because of the technology available at the time and the landscape they had to navigate.

The so–called Arch of Drusus in Rome, near the start of the Via Appia. This was an ancient road over 2000 years ago, and is still in use as a road today

Roman roads were often paved in high traffic areas leading into major cities, such as here into the ancient city of Timgad in Algeria (artist’s depiction)

The study, published in the journal Nature Communications, found that the least–straight Roman roads were found in mountainous areas in southeastern Europe.

Meanwhile, the straightest roads were located in the lowlands of western Europe and North Africa.

The analysis also revealed some cities such as Antioch, Ankara, and Byzantium were better located as central locations within the road network than Rome itself.

‘Roman roads were far more than transport routes,’ the researchers said. ‘They helped structure the movement of people, trade, technology, and beliefs across the empire.

‘Understanding how this network worked offers a new way of exploring how infrastructure can shape societies – and how decisions made thousands of years ago can continue to influence the landscapes we live in today.’

To create the Itiner–e map, the researchers used archaeological and historical records, topographic maps and satellite imagery.

They relied partly on stone ‘milestones’ put at regular intervals along roads by the Romans, some of which survive today tucked into hedgerows or even reused as gateposts, while helpful evidence includes remains of Roman ‘service stations’.

The Roman Empire was a huge territory that existed between 27 BC and AD 476, spanning across Europe and North Africa with Rome as its centre.

The map offers a snapshot of the year AD 150 – when the Empire was at its height, stretching from modern–day Britain to Egypt and Syria and including over 55 million people.

Under Emperor Claudius, the Romans invaded Britain in AD 43 and quickly set to work transforming our landscape by building cities, sewage systems, roads and more.

As the map shows, Britain’s road network was extensive in the second century thanks to the Romans, with most major highways running towards the capital city Londinium.

Now of course known as London, it was connected by the ‘Devil’s Highway’ to Calleva further west, now one of the best preserved Roman towns in Britain.

HOW IMPORTANT ARE ROMAN ROADS?

Via Giulia Augusta leading across the Pont Flavien in Saint-Chamas in southern France, is pictured above

Roman roads were large structures, typically measuring 16 to 23ft (five to seven metres) wide.

They reached a height of around one-and-a-half feet (half a metre) in the centre.

While the Romans were famous for building roads in straight lines, the discovery of a road between Ribchester and Lancaster shows they also took the natural geography of a place into account, to avoid steep hills, for example.

The roads were used to transport goods efficiently and for marching soldiers.

Preservation of Roman roads in the UK varies, with some still protruding from the land and easily visible. 

Others are hidden under earth and have only been found thanks to Lidar. 

For decades after the 43AD Roman invasion of Britain, a large region of the North, including what is now Lancashire, Yorkshire and Cumbria, was controlled by a Celtic tribe known as the Brigantes.

Roman writer Tacitus wrote it was the collapse of the marriage between Queen Cartimandua of the Brigantes – a Roman ally and her husband Venetius – that led to a showdown with Rome.

Roman roads were large structures, typically measuring 16 to 23ft (five to seven metres) wide. In the image above left, chariot ruts can be seen on the Via Domitia near Ambrussum. On the right, a view of Via Applia Antica

Following their divorce, Venetius organised a revolt in 69AD and Cartimandua fled.

The Emperor Vespasian then sent a force under Britain’s new governor, Quintus Petilius Cerialis, to put down the rebellion and conquer northern England.

Building roads to link up forts and settlements across this rugged landscape was a vital part of this decades-long conquest of the North. 

 The Romans purposefully built their roads to be very straight to make journey times as short as possible.

As compasses were yet to be invented, Roman surveyors used a piece of equipment called a groma – a wooden cross with weights hanging down from it – to help make the roads straight. 

The roads were used to transport goods efficiently and for marching soldiers.

Preservation of Roman roads in the UK varies, with some still protruding from the land and easily visible. 

Many of the roads paved direct routes between isolated regions and towns. 

This network greatly encouraged trade at the time as the travel time was slashed. 

Research has found that many of the roads that have existed for millennia have formed the backbone of economic routes to this day.