Ancient Roman architecture
Although concrete had been used on a minor scale in Mesopotamia, Roman architects perfected Roman concrete and used it in buildings where it could stand on its own and support a great deal of weight. The first use of concrete by the Romans was in the town of Cosa sometime after 273 BC. Ancient Roman concrete was a mixture of lime mortar, aggregate, pozzolana, water, and stones, and was stronger than previously-used concretes. The ancient builders placed these ingredients in wooden frames where they hardened and bonded to a facing of stones or (more frequently) bricks. The aggregates used were often much larger than in modern concrete, amounting to rubble.
Ancient technology
Roman engineers build monumental arches, amphitheatres, aqueducts, public baths, true arch bridges, harbours, dams, vaults and domes on a very large scale across their Empire. Notable Roman inventions include the book (Codex), glass blowing and concrete. Because Rome was located on a volcanic peninsula, with sand which contained suitable crystalline grains, the concrete which the Romans formulated was especially durable. Some of their buildings have lasted 2000 years, to the present day. Roman society had also carried over the design of a door lock with tumblers and springs from Greece. Like many other aspects of innovation and culture that were carried on from Greece to Rome, the lines between where each one originated from have become skewed over time. These mechanisms were highly sophisticated and intricate for the era.