This monograph is a splendid contribution to a variety of studies, from the ancient economy to topography, the building analysis of maritime structures, quantitative analysis of pottery, marble, glass and others. In pursuing a project that has now occupied him for some years and has produced two previous substantial monographs,Footnote ¹ K. has gathered once again a number of scholars to investigate the role of Portus in relation to Rome and to other ports in the Mediterranean. Whilst the first two monographs focused, generally speaking, on the structures of Portus and the relationship with the surrounding areas, the twofold aim of this study is to consider ‘how far Portus, as the maritime port of Imperial Rome from the mid-first century ad onwards, was the principal conduit for supplying Rome’ and to ask ‘how far the commercial links that fed Portus were part of a single overarching network or a series of interlinked networks that extended across the Mediterranean’ (p. 1). The publication fulfils both objectives, as long as one keeps in mind two important provisos. The first has to do with the status quo of the investigation: some of the papers are at an initial or intermediate stage of research, due to the availability/quantity/quality of the material coupled, at times, with the difficulty of applying definite methodologies. Other papers are the result of a more advanced stage of the research. The second proviso has to do with the readers' expectations in terms of geographical coverage. As the volume cannot cover every potentially relevant site in the Mediterranean, there are absences that may appear striking (for example Alexandria and the Middle East – although K. himself devoted a paper to the grain supply from Alexandria in 2008.Footnote ² This reader, for reasons outlined below, would have also appreciated the inclusion of Puteoli). However, it would be unfair to stress these biases given the far-reaching potential of the research and the analytical detail behind the papers. The volume can be viewed as both an excellent snapshot of the state of research and a promising work-in-progress.

The volume is divided into seven sections: (1) Portus and Ostia (four papers exploring the connection between the two and with Rome); (2) Ships and navigation (three papers about sea-routes within the Mediterranean); (3) Italy and Sicily (one paper about Sicily and one on Ravenna and Classe); (4) Hispaniae (five papers ranging from the movement of marble and amphorae to structural analysis); (5) Africa (one paper about pottery analysis); (6) The East (three papers on Egypt and pottery, harbours on the Red Sea, and Ephesus and Smyrna); (7) Broader issues (four papers on a variety of methodological aspects). K.'s introduction is excellent in providing both a historical and an operational context to such a variety of contributions, minimising the risk of producing what might appear – at first glance – a collection of perhaps brilliant but somewhat disjointed papers (and this is particularly true of the last section because of the wide-ranging scope of each work).

There are three major sources in K. and his team's enquiry: pottery, marble and shipwrecks. The production of a fourth, glass, is analysed for its potential in highlighting maritime routes. Unsurprisingly, archaeologists working with pottery and marble will find an abundance of material here. Marble helps us appreciate the double nature of Portus as a destination point and redistribution harbour, whilst the versatility of pottery studies finds a number of applications (pots are considered as good carriers, structural material and tracing means for the administration of the annona, for commercial routes, for the location of ateliers and the harbour stocking areas of Portus). Shipwrecks are also given appropriate space because of their potential in reconstructing sea-routes and in drawing attention to the relation between ship size and route undertaken thanks to models based on the loading process. All the topics are, of course, interlaced so as to provide a vivid picture of the level of exchanges and contacts across the Mediterranean sea which in turn reflects on the centrality of Portus as the main harbour for the city of Rome and beyond.

The first section helps us appreciate the sheer scale of changes affecting the role of the many harbours around Rome following the construction of Portus. This becomes a decisive factor for a new organisation where Centumcellae, Cumae, Tarracina and Antium undertake renovated roles in the distribution of goods for Rome. Since Puteoli, until then a major player in the supply to the Capital, is recognised as having ‘some kind of role … down to the later second and early third centuries ad’ (p. 52), a paper focusing on this harbour would have been a beneficial addition and one able to emphasise the complexity of the supplying issue.Footnote ³ And proceeding from the macro to the micro, each step of the route to Rome is impacted by Portus, up to the towpath along the river Tiber. On the opposite hand, the case studies and the investigations of sea-routes allow us to catch a glimpse of the wide network of which Portus was one – though extremely important – participant: the vitality of areas such as Asia Minor, Egypt and the Red Sea (alongside the western countries) and the overall volume of traffic well into Late Antiquity provide the framework for looking at the harbour from a wider perspective. It is this contextualisation of Portus that constitutes the most important contribution of the volume.

Another fundamental quality of the volume is the variety of methodologies presented and their potential for future research, some of which have received sporadic attention in the past and/or have been mainly employed in isolation. It is especially (but not exclusively) the papers of the last section that offer scholars a taste of the promising results deriving from the applications of, for example, geo-archaeology, computation and the analysis of productivity and connectivity. K. and his team are clearly championing the usefulness of a ‘system’ of approaches in order to investigate the complexity of the operations underlining commerce in antiquity. And though such a ‘system’ is often presented without evident links with Portus, it does not however detract from its relevance per se. From this point of view, the volume is not only a work-in-progress but constitutes a springboard for future investigation.

K. and his team are to be praised for providing a far-reaching overview of the complexity of commerce during Imperial times. New discoveries will add to the picture and help in refining some of the hypotheses presented, but all the premises are there and they constitute more than a good auspice for future campaigns.