The second century BC was a time in which "direct exposure to influences from the Hellenistic East and the already Hellenized Campagna" had increased enormously (Fletcher 212). Under this influence the Romans began to exploit the travertine and tufa that was available to them locally and to import marbles of various types from abroad. The classical orders of Greece, the Corinthian in particular, were adopted by the increasingly wealthy Romans. But the Romans were to transform architecture and take it beyond the range of forms that was readily available from the Hellenic world.
Though Roman architecture owed so much to the Hellenic world, its principal preoccupation was with the curve, which had been almost completely ignored by the Greeks for centuries. The traditional trabeated construction associated with Greek Classical architecture was to be gradually replaced by the arches, vaults, and domes at which the Romans came to excel. The use of the curve created an entirely new dynamic in architecture. In a Roman colonnade, for example, the viewer's eye can begin at any point on the column and has the option of going up or down and then, when it reaches the architrave, it has the option of moving left or right. Such units, arranged in a series, "proceed across space in leaps . . . conquering distances in a way that is alien to the slower and more methodical march of columns"