It has long been accepted scholarly wisdom that ancient Mediterranean seafarers avoided sailing during the autumn and winter months, except when dire necessity forced them to do so. James Beresford's excellent book, based on his Oxford Archaeology doctoral thesis, systematically demolishes this view, and replaces it with a far more nuanced account of the seasonal challenges faced by ancient Mediterranean seafarers. B. concludes that mariners setting out to sea between late autumn and early spring would generally have had to contend with heavier seas, stronger winds and poorer light, but these problems were nowhere near as insurmountable as the majority of modern scholars have assumed. B.'s Introduction sets out the prevailing orthodoxy which assumes that, in the words of the standard reference work, Lionel Casson's Ships and Seamanship in the Ancient World (1971): ‘All normal activity was packed into the summer and a few weeks before and after it; at other times the sea lanes were nearly deserted, and ports went into hibernation to await the coming of spring’ (270–1).

The first main chapter reviews the textual evidence for a wintertime mare clausum, showing how the sources that Casson and other scholars have cited to back up the assertion that winter sailing was very rare cannot support such a sweeping generalization. B. begins with the two most frequently cited texts: Hesiod, Works and Days 663–9 and Vegetius, Epitome of Military Matters 4.39. Both describe a sailing season of extremely short duration. In the case of Hesiod, B. emphasizes the particular historical context, rural Boeotia c. 700 b.c., as the main reason not to assume that his advice that sailing is best in the fifty days after the summer solstice was a rule that applied throughout classical antiquity. Vegetius' statements that navigation can only be deemed safe from late May to early September, and that the seas are ‘closed’ from early November to early March, are shown to have relevance only to fleets of Late Roman warships, which were much more vulnerable to heavy seas than dedicated cargo ships. B. gives due consideration to a ruling of Gratian which decrees that merchant ships should not leave port between late October and early April (Theodosian Code 13.9.3 of a.d. 380), demonstrating that it applied only to North African navicularii contracted to the Roman state, probably because the local sea conditions were far worse at this time than elsewhere in the Mediterranean. B. skilfully analyses a wide range of textual evidence for winter sailing, including the narrative of St Paul's journey from Caesarea to Rome (Acts of the Apostles 27–8), Claudius' measures to ensure a constant grain supply in Rome (Suetonius, Claudius 18–19) and a passing reference by Pliny the Elder to greedy merchants daring to sail the seas in winter (Natural History 2.47.125).

Ch. 2 employs a wealth of modern meteorological and hydrological data to reveal the regional diversity of Mediterranean winter seas, which means that areas such as the Levantine seaboard typically experience much better sailing conditions than the Gulf of Lyon (Sinus Gallicus). These points are vividly illustrated by an excellent selection of maps and tables. The third chapter, also well illustrated, demonstrates that Mediterranean ships and sailing rigs improved significantly after 700 b.c., so that most merchant ships of the late Hellenistic and early Roman imperial periods were bigger, sturdier and more able to manage rough seas than earlier vessels. Ch. 4 assesses the various means by which ancient mariners could have met the challenge of navigating a course in winter, emphasizing the skilled deployment of local knowledge of both land and sea, details of which are not found in any texts or documents because they were transmitted though oral traditions.

Ch. 5 argues that the substantial evidence for ancient trading voyages to the Indian subcontinent, exploiting the south-west monsoon, implies that the ships and seamen involved could cope with very stormy seas on a regular basis, lending further support to the main argument that Mediterranean mariners had the means to manage winter sailing conditions, given sufficient motive. The sixth chapter considers the evidence offered for seasonal variations in the activities of ancient ‘pirates’ and ‘fishermen’. The former are held to be likely to encourage merchant vessels to sail during winter by their absence, and the latter prove, by their seasonal pursuit of migratory fish, or their year-long quest for lucrative murex and purpura, that winter seafaring was a regular practice.

Having established a new, superior orthodoxy that acknowledges a much longer ancient sailing season, with significant local variations, B. reflects in his conclusions on the economic implications of his findings. Shipwrights, chandlers, sailors, merchants, port workers, maritime financiers and all those who were involved, directly or indirectly, with ancient maritime commerce may have had less to do from late autumn, but they certainly did not go ‘into hibernation’ until spring.

Shipsheds, structures that housed oared warships, were an essential component of the military infrastructure of any ancient naval power, large or small. Shipsheds of the Ancient Mediterranean is the principal publication arising from a major research project based at Royal Holloway, University of London, largely funded by the Leverhulme Trust, directed by David Blackman, Jari Pakkanen and Boris Rankov, with Kalliopi Baika, Henrik Gerding and Judith McKenzie as research assistants. In many ways it is a follow-up to John Morrison's quest to understand the ancient trireme, which culminated in the building in 1987, and subsequent sea trials, of Olympias, a reconstruction designed by John Coates (J. S. Morrison, J. F. Coates and N. B. Rankov, The Athenian Trireme. The History and Reconstruction of an Ancient Greek Warship (2nd edn, 2000)). Blackman's research on the dimensions of extant Athenian shipshed remains was a key element of the reconstruction and Rankov was rowing master on Olympias.

The volume has two distinct parts. Part A: ‘Study’ comprises thirteen chapters, the first three of which introduce the subject, outline modern research and survey the history of shipsheds, focusing on the fairly abundant literary and archaeological evidence from the Greek world. Chs 5–13 discuss the construction, fortification and use of shipsheds, including rock-cut slipways. Part B: ‘Catalogue’ presents textual and archaeological evidence for twenty-four sites, mostly in the eastern Mediterranean, where shipsheds have been definitely identified, almost all dating to the Classical and early Hellenistic periods, followed by brief discussions of seven probable, eighteen possible and seventeen unlikely identifications, plus one undoubtedly false identification.

Readers of this journal will probably be most interested in, and somewhat disappointed by, ch. 4, on Roman shipsheds, by Rankov. Literary texts indicate that shipsheds existed at Rome, probably on the Campus Martius, in the Republican period, perhaps as early as the mid-fourth century b.c. and certainly by the end of the third century b.c. They became redundant when Augustus established naval bases at Ravenna, Misenum and Forum Julii (Fréjus), but no shipsheds have been excavated at those locations. Epigraphic evidence suggests the existence of shipsheds at lesser fleet stations, such as Aleria and Mainz. Roman Republican fleets undoubtedly utilized existing Mediterranean shipsheds, including, perhaps, some of those in the main catalogue (Kos, Massalia, Rhodes). Rankov surveys the possible iconographic evidence (coins, mosaics, wall-paintings and relief sculptures) in a highly sceptical manner, firmly accepting only the portrayal of vaulted buildings in the background of scene 79 on Trajan's Column, showing Trajan departing by ship at the start of his Second Dacian War (a.d. 105–106). The location of these shipsheds is impossible to determine, although it is most likely a Roman fleet base such as Misenum or Ravenna. Rankov's cautious approach to this material is justified, although this reviewer feels that he goes too far in some cases, even rejecting three fresco panels from Pompeii, now in the Museo archeologico nazionale di Napoli, that depict a row of warships framed by arches and (possibly) supported on props (38–9). Rankov laments the lack of definitive archaeological evidence, casting an equally sceptical eye over putative Roman shipshed remains from the Tiber to the Danube. He speculates that the Romans built relatively few shipsheds compared to some of their Mediterranean neighbours, whose facilities the concentration of naval forces under the Principate, coupled with the benefits of the Pax Romana, will have rendered redundant also, hence the evidence of demolition and replacement by other structures at places like Kos (368–9), Sicilian Naxos (405) and Rhodes (513).

Each chapter and each catalogue entry has its own bibliography, which suits the book's function as a reference work. The ten-page index is useful, but it is far from comprehensive, and the choice of entries and selection of references for many of them struck this reviewer as odd. For example, every passing mention of a modern archaeologist is fully indexed, but anyone wishing to pursue the topic of ‘dividing walls’ in depth will find that the index entry refers only to a few pages of ch. 8, and omits the numerous mentions and discussions of these important features in the Catalogue.

Three maps at the front locate most places referred to in the text, and the book features numerous plans, reconstruction drawings and photographs. Many of the plans have been adapted from other publications by Judith McKenzie, whose status as a co-author is acknowledged by the cataloguing-in publication entry, although her name and biographical details are missing from the front cover and end flap of the dust jacket.

There can be no doubt that this superb volume will be the standard work on the subject for the foreseeable future, and that it will both enable and encourage further research, hopefully including the discovery of the elusive Roman shipsheds.

The subject matter of these two books occupies only a few pages in Casson's, Ships and Seamanship in the Ancient World. Since that seminal publication appeared, however, new material has come to light, and new methodologies have emerged that enable much fuller and better treatments. Both books display scholarship of the highest quality and represent major advances in our knowledge and understanding of the ancient maritime world.

I conclude with a look at the cataloguing-in publication entries for these two important books. Shipsheds of the Ancient Mediterranean has been classified under the Hydraulic and Ocean Engineering subset of Technology (Library of Congress TC216), or Military and Nautical Engineering (Dewey 623). The Ancient Sailing Season has been assigned to Navigation History (Library of Congress VK16), or Water, Air and Space Transportation (Dewey 387). Does this reflect the increasing ‘interdisciplinarity’ of Classical research, or the frustrating limitations of library cataloguing systems?