The Romans became famous for many of their engineering advancements. They used the arch in their building to build higher and stronger structures such as the Coliseum. The Romans extended the idea of the arch into the dome. The Pantheon, originally a temple to the Roman gods, was the largest dome built until the twentieth century.
Another advancement in Roman construction was their use of concrete. The Romans were able to utilize this less expensive and very strong material to develop structures that were much more durable than wood constructed counterparts. The process of pouring the concrete was not much different than current day. Concrete walls were built by pouring a footer at the foundation. After the concrete hardened, they built wooden scaffolding or supporting framework. They lined the scaffolding with bricks and poured the concrete in between. After that layer hardened, the workers extended the scaffolding to make the wall higher.