On noting the adjective ‘enigmatic’ in the title of an excavation report, the prospective reader can be gripped by two contrary sensations — either that a detailed study of the contents by a fresh pair of eyes will reveal more answers as to the site's true character, or that the reader will remain, at the end, as baffled as the excavators were. In essence this is the eternal struggle that hope enjoys with experience. In this case, as in many others, it is experience, alas, that triumphs.

First of all, the plaudits. The excavation was carried out by the authors and members of the Association for Portland Archaeology (APA). It was a community-led project, and the amount of data we have from the site is a credit to this largely voluntary force. The project took place in the corner of a large sports field at Royal Manor Arts College in Weston Road, Portland. Excavation was undertaken because of a proposal to lay an all-weather sports field. Commercial archaeologists were initially on-site to do a ‘watching-brief’ during topsoil stripping, and one can sense a car-crash moment when the stripping immediately revealed remains of round and rectangular buildings, as well as quantities of Late Iron Age and Roman pottery. In the end, the quality of the archaeology instantly revealed was such that the proposed sports field was relocated, and the APA got to work on examining what had been surprisingly discovered. It was very soon after that point that the head-scratching started.

The real problem lay in the comparatively small size of the area excavated — c. 30 by 20 m. The archaeology was complex — limestone foundations of one complete roundhouse and half of a second, with most of the south-eastern quadrant of the site occupied by the stone foundations of a medieval rectangular building. In addition there were pits for graves, odd lengths of wall, a sizeable ditch, and a great quantity of finds. The excavation had revealed what was clearly a small part of a much larger site. In summary, several crouched inhumations were located, which appear to fit with the characteristic burial-rite of that part of southern Britain in the Late Iron Age. The roundhouses were dated by the excavators to the early Roman period, although conceivably they concealed earlier, Late Iron Age, foundations. Occupation in the Roman period lasted into the fifth century, and several ‘baby-burials’ were associated with the early ‘Roman’ period. Four out of the seven baby-burials were directly linked with structures, one possibly a domestic oven.

The format of the report leaves much to be desired. After a brief introduction, the text first deals with the structures and then has lengthy but divorced sections on the environmental and artefactual finds; with more detailed post-excavation material on an accompanying CD. The more interesting of the specialist reports concern the animal bones (a lot of fish and sheep) and the samian report (a lot of high-status decorated bowls and dishes, but few cups). Plans and photographs are bunched at the back, meaning that the reader constantly has to flip between text and images to gain a clearer understanding. The report is prefaced by a dreadfully over-enlarged map of Portland.

What larger whole are these roundhouses part of? Who used them and precisely for what? What kind of site is this? The answers are not forthcoming. The authors are inevitably much more comfortable measuring and describing the foundations and finds, rather than attempting any definitive synthetic interpretation. When suggestions are made, they are so heavily circumscribed by doubts and alternatives that the reader rapidly loses confidence in them. Too many caveats create a labyrinth of possibilities and the reader risks getting lost. Even the purpose of the rectangular medieval building remains elusive.

The value of this report surely lies in the future, when more of the archaeology of Portland Bill is known, and a much more coherent view can be established of the nature of its occupation in the Late Iron Age and Roman periods. Maybe at that point this piece in the jigsaw can be slotted in and we can all nod knowingly at the moment of revelation. For the time being this site remains an annoyingly frustrating part of a much larger puzzle.