Modern perceptions of the ancient Piraeus have been monopolised by the urban image and function of the port as the naval stronghold of Classical Athens. Existing scholarship so far has tended to consider the post-Classical centuries, especially the era following the sack of the port in 86bcby the Romans, as a period of decline. Such preconceptions, based on largely superficial readings of a few ancient literary texts and a near-total disregard of the material evidence, have created a distorted image of the Piraeus and its significance in the Roman period. Drawing upon textual sources as well as archaeological evidence, this paper explores the changing nature of urban settlement, maritime functions and the economy of the port from the time of its destruction in 86bcto around the sixth centuryad. Particular emphasis is placed on a re-examination of the existing evidence from rescue excavations conducted by the Greek Archaeological Service as they relate to the topography of the Roman port and its long-term evolution. This combined study offers a more complex picture of the infrastructure, urban image and operational capability of the port during the Roman period than was hitherto possible. It also permits a more balanced understanding of the port's function at local, regional and provincial levels, and thus enables comparisons with other Roman ports in the Aegean and the rest of the Mediterranean.