Roman Bridge Pont du Gard in France. Credit: JackF / Adobe Stock

6 Ways Roman Engineers Were Way Ahead of Their Time


Ancient Roman engineers were able to construct many different kinds of remarkable structures which have stood the test to time. In many places around the world we can still see and admire their incredible knowledge of engineering and technology. This shows us that the ancient Roman engineers had a superb understanding of how to build a vast range of buildings - plus their famous aqueducts - which we still marvel at today.

However, in order to understand the range of skills and technology available to the Roman engineers, it is necessary to recognize that they turned to the engineers who preceded them; to study their ingenuity and skills so that they could find ways to improve upon the skills and inventions of the past. To do so, just like engineers in today’s world, the ancient Romans had to find and develop more sophisticated means and see how they could discover new materials that would be required in what we call civil engineering today.

Roman engineer's bronze compass. (Mary Harrsch/CC BY NC SA 2.0)

Roman engineer's bronze compass. (Mary Harrsch/ CC BY NC SA 2.0 )

With their new discoveries, they also had to come up with new techniques, which would completely change the way that buildings and bridges were made, and the vast range of equipment needed by the military and navies of the Roman Empire. Such engineering skills would see the birth of new machines, like developing water power as a means of energy. Such simple things that we take for advantage today, like plumbing and running water, would have been a huge advantage for the average Roman. How would people today survive without these things?

Through these changes, those ancient Roman engineers would see their work rewarded, as more prosperity and greater wealth came into play. Also, their engineering skills would directly improve the lives of all Roman citizens and show the nations trading with Rome that this knowledge gave them greater power.

Roman Roads Helped Transport and Trade

One of the great improvements to ancient society was the building of roads which were well thought out and well built. The vast majority of roads were made with cut and dressed stones, but there were also concrete roads. Such civil engineering skills by the building of these roads also lead to greater commerce within the Roman Empire and allowed the merchants to reach ever further out and expand trade. In the time of ancient Rome those roads were considered so important that some 29 roads were made to lead to and from the eternal city.

An ancient Roman road. (Alex /Adobe Stock)

An ancient Roman road. ( Alex /Adobe Stock)

Ancient Roman Engineers Created Awesome Aqueducts

We all know that if we are to survive it is essential that we all have access to water. Before the Romans built their own aqueducts these structures existed elsewhere in the East, for example the famous Aqua Appia was thought to be built around 310 BC. However, we can thank ancient Roman engineers for their new innovations, which enabled them to build larger constructions more quickly.

This required the employment of many different skilled craftspeople, from stone masons to carpenters and metal workers. They all came together to build aqueducts far from the cities where people lived. This also meant the skill of the engineer had to pan and execute for those craftsmen, as the aqueducts used the power of gravity, unlike today where we use pumps.

Aqueduct Pont du Gard - Provence France. (Nikolai Sorokin /Adobe Stock)

Aqueduct Pont du Gard - Provence France. ( Nikolai Sorokin /Adobe Stock)

But building such structures also meant the engineers had to draw up plans for their continual maintenance and keep them free from debris, which would otherwise accumulate and slow down the supply of clean and safe water. Between such large structures the ancient Roman engineers built a network so that water could be changed over to another system if the need arose.

The Coliseum is Standing Proof of Roman Engineering Ability

The Coliseum is one of the most amazing buildings of ancient Rome that still stands for us to marvel at today. Its main function was to provide entertainment, like other vast stadiums. It saw gladiator games, plays, and even mock battles between ships when the arena was flooded. This last event was another incredible feat of engineering in itself - to allow for water to both flow into the arena but also for its drainage system.

It was constructed of stone and it is thought to have easily accommodated some 50,000 spectators. The Coliseum is an incredible feat of masonry showing the structural engineers had a sound understanding of arches and the material strength and durability of the stonework. It is estimated to be about 620 feet (188.98 meters) in length and some 515 feet (156.97 meters) in width, with a height of nearly 158 feet (48.16 meters).

The Coliseum is one of the most famous examples of great Roman engineering. (phant /Adobe Stock)

The Coliseum is one of the most famous examples of great Roman engineering. ( phant /Adobe Stock)

Although there are signs of decaying in some areas, this is not attributed to the skills of the ancient craftsmen. The deterioration of the Coliseum is due to time and not a representation of any bad workmanship or failings on the calculations of the ancient Roman engineers who built it.

Highly Versatile Concrete was a Major Advancement

The builders of ancient Rome made what must be one of the major discoveries with the invention of concrete. This discovery changed the world. By the 3rd century BC, they found that the addition of water to the dust from volcanoes, plus other ingredients such as small parts of bricks and stones, along with lime, created a change in the chemical structure which gave them the perfect mortar.

This was a revolution in concrete. They also discovered this worked well for the Roman builders working with water and even underwater constructions, like at the quay sides at harbors and the cities which were built along sea fronts. Another use for Roman concrete was to waterproof all the cisterns, known as Pozzolana.

By the time of the 2nd century BC, the Roman engineers and builders had mastered the art of building large and magnificent stone bridges; for example the Pons Aemilius in the city of Rome. At first, the large stones were held together by a series of iron clamps inserted into the stones, but the discovery of concrete changed the way they could build such large structures.

The Pons Aemilius. (duke2015 /Adobe Stock)

The Pons Aemilius. ( duke2015 /Adobe Stock)

Now they could build the bases from super strong concrete and use stones for the facings. The Roman engineers were among the first to fully understand that when it came to arches while building bridges they could use different shapes of stones; these were called Voussoirs. This created strong arches which would distribute the weight efficiently. Such arches can still be found in Europe today, demonstrating the incredible skill of those builders and engineers as well as the strength of the materials to create something that could endure centuries of weather.

The continued expansion of the Roman Empire would require the builders and ancient engineers to construct a vast array of buildings, structures, and roads from materials that were both strong and also durable. As we see in today’s civil engineers and construction companies, the ancient Romans must have also understood the science and studied how different materials work.

These ancient Roman builders and engineers were more than impressive in how they managed both durability and strength to create their structures which we can still marvel at today. Also their discovery of concrete enabled them to build not only large buildings and arches but also very large domes.

Roman aqueduct by Robbie Peterson (Author supplied)

Roman aqueduct by Robbie Peterson (Author supplied)

This allowed them to create much more space within the interior of the structures. We can find examples of this work in buildings such as temples, atriums, and amphitheaters. There are a number of large Roman stone bridges still standing today - one magnificent example was built to honor the Roman Emperor Trajan.

This was built with segmented arches joined up together, and the builders used both stone and concrete in their construction. It crossed the river Danube and was some 3725 feet (1135.38 meters) in length, nearly 50 feet (15.24 meters) in width, stood some 60 feet (18.29 meters) above the water, and two castra (military camps) were constructed at each end. This impressive feat of engineering began around 105 AD, when the Roman army was fighting the war in Dacia, so Trajan required this bridge to supply and maintain his war effort.

Tunnels Prove Ancient Geometry and Surveying Skills

The creation of tunnels were one of many engineering projects that the Romans had to devise in order for the supply of water to reach the aqueducts. It was a considerable feat of engineering and construction that saw the Romans tunneling through hills and, if needed, even mountains. The method was similar to the system they used to build lines for straight roads: they laid out a number of posts at given intervals and this gave them straight lines. Even more remarkable, while tunneling they also constructed vertical shafts which brought fresh air to those actually doing the physical labor.

The Romans had investigated how the Persians had bult their tunnels. By understanding their work, the Roman engineers could ensure the vertical shafts were always in line with the tunnels. Just as in many operations today, when faced with tunneling through a mountainside, the Roman builders used a method called counter-excavation, which sets teams of construction workers digging towards each other from the opposite sides of the hill or mountain. In order for the Roman engineers and builders to accomplish such projects they had to have a detailed knowledge of geometry and surveying.

Major Roman tunnel on Mount Salviano. (Claudio Parente/CC BY SA 4.0)

Major Roman tunnel on Mount Salviano. (Claudio Parente/ CC BY SA 4.0 )

To deal with the hard rock that was encountered while tunneling, one of the techniques used was applying heat (fire) to the rock surfaces, followed by a rapid quenching of the fire with cold water - this caused the rocks to crack. This work was done by Roman workers and slaves and could take a very long time. An example of tunneling is when the Emperor Claudius drained Lake Fucine in 41 AD. It is estimated to have taken some thousands of workers and builders nearly 12 years to complete.

Roman Weapons Made Conquering Foes Easier

Over the centuries, the ancient Romans were able to build up a very formidable range of weapons through the knowledge of its engineers and craftsmen. By such skills, the working knowledge of different kinds of materials, and their knowledge of metallurgy, the Roman army and its naval counterparts could call upon some of the best weapons available at that time in history. Having access to this range of weapons allowed the Roman legions and the imperial fleets to not only conquer their foes but also to expand the Roman Empire.

One example of a weapon which is an amazing feat of technology is the “ Ballista.” Originally used by the Greeks, the Roman engineers greatly improved its function and versatility by making alterations to a number of the metal components. This not only increased its range but also made it lighter and much more manageable for the legionary gun teams. There were a number of differing models of this weapon and the larger models had a firing range of some 1476 feet (450 meters).

Another awesome weapon in the legions’ armory was the Onager. This could launch heavier objects or projectiles than its smaller cousin the Ballista. It was simpler in construction and therefore easier for the crews to operate this weapon. It has been calculated from its swing that the arm could launch a stone of some 55 lbs. (25 kg) that would damage and smash down enemy fortifications. Because it was a large and heavy weapon, it would be assembled on the battlefield by the Roman engineers.

‘The Catapult’ (1868) by Edward Poynter. (Public Domain)

‘The Catapult’ (1868) by Edward Poynter. ( Public Domain )

We must remember that the Roman Empire was also built upon its naval powers and the maritime shipbuilders – which led to the two main bases at Misene and at Ravennate. We can still see this maritime technology by visiting the Ancient Roman Naval Museum by Lake Diana near Rome.

Top Image: Roman Bridge Pont du Gard in France. Credit: JackF / Adobe Stock

By John S. Richardson

John Richardson’s recently published book,  The Romans and The Antonine Wall of Scotland  , is available from  Amazon.


J.P. Oleson  The Oxford Handbook of Engineering and Technology in the Ancient World. Oxford University Press. 2009.

D.S. Robertson. Greek and Roman Architecture. Cambridge University Press 1969.


Gillian Holmes's picture

Of course they weren't 'way ahead of their time' they were of their time, what else could they be?

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