The Romans learned most of their architectural techniques by the Etruscans and the Greeks, which were two civilizations that existed prior to the formation of the Roman Empire. Once the Roman Empire was formed, it extended over Etruscan lands and Greek city-states. As a result, Roman architecture shares very similar themes with Greek architecture.
In modern society, we almost always associate the architecture of Ancient Rome with arches. This is no accident, for the Romans had developed and widely used arches in the beautification of their architecture. More importantly, though, Romans discovered that arches were good to use in balancing and supporting weight from above. From this discovery, Rome created some of the greatest bridges in the ancient world. Also, another structure that used the versatility of the arch was the Roman aqueduct. The Romans cleverly used arches and aqueducts to transport water from one area to another. It was the first civilization to do such wonders. Furthermore, the Romans continued to widely apply the arch to Roman architecture. In residential buildings, Romans developed vaults, which are arched roofs, and triumphal arches were developed to honor figures, such as war heroes or other leaders. Could the Arc d'Triumphe in Paris, France be connected to the Triumphal Arch? [Hint: The Roman Empire stretched into all of Gaul - (present-day France)].
As we now know, the Ancient Greeks greatly influenced Roman architecture. This can be examined by the columns found on Roman buildings, that are similar to the Greek orders. In addition, the Romans developed two more of their own orders based on the Greeks. These are Tuscan and Composite.
This picture of the Roman Colosseum graphically displays their use or arches and columns.
As such a mighty empire prominent in the ancient world, Rome encompassed lands primarily surrounding the Mediterranean Sea, including North Africa, Europe, and the Middle East. Through centuries of Roman rule, Roman culture was spread throughout many of these areas. Since Roman culture was based on Greek culture, Greek culture too was spread into many of these lands. Conclusively, many examples of Greek and Roman architecture will be exhibited in France, Spain, Egypt, and beyond. It is now evident that as architecture is part of a people's culture its is also tightly knit with global history. However, one can still ponder about how Rome kept such a grand empire and managed so many different cultures . . .
The answer lies with in another aspect of Roman architecture. Rome tied up its empire in an extensive road system, which allowed for the rapid transfer of communication, ideas, and even architectural styles. This exchange of ideas, called cultural diffusion, made Rome as strong as it was and made Roman architecture as prominent as it was. This is the legacy of Roman architecture.
Did you know that concrete was a Roman invention, which led to development of bricks? In the modern world, most houses are made from brick as it gained popularity during the late nineteenth and twentieth centuries.