3.2.3 Period 3. Iron Age

Commentary on the Site Description (2008)

Overview | Enclosure ditch (inner) | Inner ditch recutting | Bank | Inner annexe | Palisade I | Gateway | Palisade II | Outer ditch | Internal structures | Pits | Iron Age structural discussion Internal structures (Period 3)

Since at best only vestigial occupation levels survived at Blackstone (see above) the evidence for structures of any kind consisted solely of post-footings of various types. The majority (67%) of postholes were 0.10-0.29m deep, measurements which were probably within 0.10m of the original depth. Erosion in this soft subsoil made the original diameter of these features much more difficult to estimate, as were size and section of timbers used in these structural features. If post-impressions in the bottoms of some post-footings could be trusted, most posts had a round cross-section. Those in features 1551 and 1032 show that posts of square and triangular cross-section (longitudinally cleft timbers) respectively were in use. Other more loosely associated post-settings were described as 'clusters' and are listed in the archive.

Grouping the postholes

Some post-footings could be grouped, according to type, size and spatial relationship into 'buildings' (e.g. building 1 or BG1; Table 1). These were initially identified from spatial patterning of post-footings followed up with some typological and dimensional similarity. Comparisons were based on the dimensions of the post, where these could be inferred from post-impressions, and only secondarily on the type of post-footing. Some pairings of postholes and pits have also been suggested (Table 1).

A few stakeholes were recognised, and, although they were difficult to distinguish in the gravel, no large numbers were considered to have gone unrecognised. Consequently it is not believed that any stake-walled buildings existed in the excavated areas.


The majority of the buildings (as identified in 1979) were founded on shallow, fairly widely spaced post-footings, and the small dimensions of the structures might be thought to reflect unsophisticated building techniques. Building 3 is a four-poster but the extreme shallowness of its post-footings (they are probably post-sockets rather than postholes) sets it apart from the others of this plan-type, as does its rectangular shape as opposed to the usual square (cf. four-posters at Credenhill Camp, Herefordshire; Stanford 1970). Dimensionally the rectangular structures buildings 2 and 4 are similar.

The semi-circular buildings, buildings 1 and 5, are of a type known elsewhere, the closest example being at Caynham Camp (Shropshire; Gelling 1965) where a multi-phase building, utilising in its several phases post-in-pit and post-in-slot construction, was tentatively interpreted as a shrine. In other areas such buildings are more often associated with industrial uses, such as at Gun Hill, Essex (Drury and Rodwell 1973) and at Barley, Herts (Cra'ster 1961), where the evidence was considered to represent iron working.

A small ring gully (0237; Figs. 11 and 31) held posts for a heavily constructed hut with an internal diameter of only about 2m. This had an entrance to the north. It may be earlier than the other buildings, and the difference in building technique might support this. It could have been used as a storage shed, being too small to inhabit, and in this it would be analogous to the smaller variety of four-post structures.

There is, then, a variety of building types at Blackstone. The congruous plan-relationship between most of the buildings, a central space, and the defences suggest a 'planned' settlement layout in Period 3, although the buildings need not all be exactly contemporaneous in construction or use. Whether any were used for domestic habitation is open to question. None of the suggested buildings contained a hearth, even though some evidence of hearths surviving on the site was recovered, at least in the north part of the enclosure (i.e. hearth 2009). Variable plan-types suggested either that building techniques evolved over time, or that buildings were differently designed for specific functions.

The buildings were, therefore, remarkably unlike those on other sites in the area. Four-posters of the Croft Ambrey or Credenhill type were absent (Stanford 1970 and 1974), although these are considerably earlier than Blackstone, and in other parts of the country tend to be a middle Iron Age fashion. Roundhouses, such as recorded at Beckford (Britnell 1974; Wills in prep. [2010]), are also not obviously present at Blackstone. Of course these may have existed in unexcavated parts of the site, but since the areas excavated in 1977 were laid out so as to leave no substantial part of the site unsampled, it can be concluded that buildings in the unexcavated areas were neither numerous nor very large. Substantial earth-fast structures are known to have existed from such deep postholes as 0069, 0260 and 0404 (Fig. 11), but such postholes never fit into recognisable plans of buildings.

Other timber structures

These comprise gullies and more or less irregular scoops that seem to have supported posts. Feature 2037 (D8; Fig. 12) shows post-pipes with post-impressions at their base. Elsewhere, evidence for posts was confined to post-impressions, and these were by no means universally present. Gullies 0146/0180 and 0178/0179 (Fig. 10), for example, have no post traces, except for the deep posthole 0466 at one end of 0179. If these were foundations for structures, they must have been extremely light in weight, perhaps simple windbreaks, since the lack of post-impressions suggests that no great weight of timber was supported. There were some exceptions, such as 0132 and 0104 (Fig. 10) which seem to have supported much heavier posts, if the deep, asymmetrical profile is indicative of the former presence of uprights packed to one side of the foundation trench. These features were quite convincing as post-footings, but it ought to be stressed that few of the slots, gullies, scoops or postholes have produced any conclusive evidence of what form of structure gave rise to the surviving archaeological evidence.

Overall comment on spatial patterning of possible built structures

The evidence from these, admittedly partial, excavations suggests that there was a marked concentration of post-footing evidence in a strip of varying width inside the line of the southern inner bank. In contrast there was little sign of Iron Age activity in the vicinity of F5 and F6, suggesting that this was an open space more or less in the heart of the settlement and conveniently located opposite the entrance.

While the postholes and settings and other similar features clearly represent much activity within the enclosure over a relatively short time period, it is difficult to form an overall view as to their purpose and function on the site. Some buildings have been reasonably reconstructed from this evidence, and it seems likely that others are hidden in the general spread of features. If they represent larger structures they cannot all have been in existence at the same time, thereby indicating that the site was undergoing quite regular, if not constant, re-organisation during its lifetime. The lack of clear roundhouses, four-posters or other recognised Iron Age types of structure could be taken to mean that the site was not an ordinary farmstead (see also Commentary and Site Discussion for further consideration of this).


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