What is a revolutionary development in Roman architecture?

One of the most revolutionary developments in Roman architecture is the use of concrete, particularly in the construction of the Roman dome. Roman concrete allowed for the creation of massive, durable structures without the need for large stones or extensive external support systems. This innovation led to the construction of iconic buildings such as the Pantheon in Rome, which features an enormous dome with an oculus at the top, demonstrating the potential of concrete in architectural design.

Extra: The Romans were incredible engineers and architects, and their use of concrete changed the course of architectural history. Roman concrete differed from modern concrete in its composition, typically consisting of a mixture of volcanic ash (called 'pozzolana'), lime, water, and various aggregates. This made Roman concrete less brittle and more capable of withstanding the test of time, as evidenced by many Roman structures that still stand today.

The introduction of concrete also led to other significant architectural features such as the arch, the vault, and the aqueduct. Roman arches allowed for the construction of large openings without compromising structural integrity, leading to spacious interiors and the ability to span long distances with bridges and aqueducts. Vaults and domes created expansive, uninterrupted interior spaces, a considerable aesthetic and functional improvement over flat ceilings.

The massive infrastructure projects like roads, bridges, and aqueducts that dotted the empire were made possible by these advancements. The extensive network of roads allowed for effective administration of such a vast territory, while the aqueducts brought fresh water to cities, improving hygiene and public health.

The Roman architectural concepts of form, function, and innovation continued to inspire builders throughout history. Many of the principles and techniques developed during Roman times were revived during the Renaissance and continued to influence architecture into the modern era. The use of concrete has been refined and developed over the centuries, but its fundamental application in architecture owes much to those Roman pioneers.