Subscribe now for full access and no adverts
Four years into our excavations at Sizewell C, near Leiston on the Suffolk Coast, Oxford Cotswold Archaeology (OCA) has so far examined some 140ha (350 acres) across 75 separate areas. This fieldwork builds on seven years of initial evaluations, and while several substantial investigations remain to be tackled, all of the sites explored so far are now undergoing post-excavation assessment, a phase that is due to be completed in the next three years. The scale of this long-running project is mirrored by the extent and diversity of the archaeology that has been uncovered to-date, some of which I will outline here.
Our principal excavations lie within a 12 square kilometre block located between the villages of Sizewell, Leiston, and Theberton, as well as the Minsmere Nature Reserve, while further links extend along the routes of the Sizewell Link Road and the Two Village Bypass, and at new Park and Ride sites at Darsham and Wickham Market. While these latter schemes are necessarily linear or discrete, what sets this project apart is that the main programme stretches across a single, uninterrupted expanse of land. For the first time in this region, we can examine archaeology on a landscape scale, understanding how this area was used from the Early Neolithic to the present day. Across a broad sweep of varied geology and topography, patterns of occupation start to emerge – and, with them, the possibility of addressing archaeology’s fundamental questions: questions that are echoed by the subtitle of this article.
The landscape’s geological diversity is as important as its geographical scope. Were the project flipped to the west, it would sit entirely on the Lowestoft Formation Diamicton – the boulder clay of Suffolk’s central ‘uplands’ – and its archaeology would look very different. In particular, it would be lacking in early prehistory: the people of the Middle Iron Age were the first to leave a major archaeological footprint up there. As it happens, though, we occupy the eastern fringes of that clay, encompassing the underlying glacial sands and gravels and, further east still, the Pliocene Crag sands; peats and alluvial soils also infill the deeper valleys towards the sea. Within the outline of our investigations, the land falls c.20m to sea level, and the resulting variation in subsoil and contour creates distinct archaeological niches. Put simply, only certain people do certain things in certain places, due mainly to underlying soil conditions and the availability of water.
What follows is only a snapshot of our ongoing work, but it offers glimpses of the excitement and archaeological potential already visible, and of some of the directions in which our research may lead. This story will change over time. It may change tomorrow. That is the nature of archaeology.
Earliest activity
At Sizewell, the Neolithic arrives with a bang and departs with something of a whimper. Fragments of Early Carinated Bowl occur in a handful of places, sometimes alongside stylistically later Plain Bowl forms, but these traces are slight, almost will-o’-the-wisps. The true ‘Big Bang’ at Sizewell comes around 3800 BC, in an explosion of pit-digging accompanied by tree- and scrub-clearance. The people who were modifying the landscape in this way had arrived with the full ‘Neolithic package’ of pottery, grain, and domestic livestock – and they came from the sea.
We have excavated four main areas of Neolithic activity so far, strung along the 14m–18m (46ft–59ft) contour on the sandy gravels, just below the diamicton, as well as a dozen smaller sites. Adding to this picture, a longbarrow, one of only a handful known in the county, lies on the edge of this zone of occupation (A on the plan on p.23) The main sites are represented by groups and loose scatters of numerous, small, ‘standard’ Neolithic pits, which are here interpreted as latrine pits. Some of these are accompanied by much larger storage pits, which are among the project’s most visually striking discoveries. Measuring up to 2.4m (8ft) in diameter and 2m (6.5ft) deep, these vertically sided, flat-bottomed features had been deliberately and rapidly backfilled with clean sand, midden waste, and burnt material at the end of their use-life. Our most plausible interpretation of their purpose is overwinter grain storage, located next to fields that were being prepared, ploughed, planted, weeded, and harvested by the same people who dug the latrine pits – contentious, perhaps, but compelling.
The largest, and perhaps most permanent, of these early sites (B) produced a dozen storage pits and at least 100 ‘latrine’ pits, along with a wealth of material evidence: some 3,000 pottery sherds, more than 10,000 struck flints, five polished axes, and a substantial saddle quern with pounder. This concentration of activity lies lower on the slope beside what would have been a seasonal stream, at a location where a well could have been sunk into the water table. Water is scarce in this landscape, limiting more permanent settlement to a few specific locations, such as this one. We can already see differences between the finds from this location and other large, broadly contemporary sites 0.7km (0.4 miles) and 1.3km (0.8 miles) to the east, which bodes well for future research into whether activities at these places varied as well, hinting at the specific reasons that people were active at each location. Different toolkits, numbers of people, and lengths of stay would be required to plant a field, weed it, harvest it, and process the crop, or to coppice a woodland and harvest it for firewood or timber for fences and other construction. Exactly the same questions can be posed to the project’s Beaker period and Iron Age archaeology, too.
Further storage pits were found within the valleys along the Link Road route to the north. Today, these areas are seasonally waterlogged – one such pit has been under water all winter – which might raise eyebrows: why put sunken storage pits on land prone to flooding? The answer lies in long-term hydrological change: 6,000 years ago, these now-wet coastal valleys were part of the high, dry uplands, then located kilometres from the coast.
The peak of Early Neolithic activity at Sizewell was intense but brief, spanning perhaps 200-300 years from 3800 BC-3600/3500 BC. We can trace this occupation through a shift from Plain Bowl into Decorated Bowl pottery, but after this the Neolithic evidence collapses dramatically and the archaeological signature remains faint for some 1,400 years, with just a handful of Middle and Late Neolithic features and findspots recorded. While this does not necessarily imply that people were not still here, it does indicate that, if they were, they were living their lives in very different ways. It is tempting to link this absence of obvious presence to the thin, sandy soils becoming exhausted after an intense 200 years of farming, perhaps allied to a shift in climate. We might imagine a decreased reliance on arable farming, too, in favour of more ‘light-footprint’ pastoral activity. Arable farming creates pits, and pits produce artefacts; pastoral farming does not.
An organised environment
The next rush of activity comes in the early Bronze Age, around 2300-2200 BC (though radiocarbon dates are not yet in), during the Beaker period. Significantly, it is unlikely that there had been forest regrowth since the Neolithic period; it seems that the Beaker folk had moved back into the same kind of areas, though not the exact same locations, that had been occupied before.
Also like in the Neolithic, the main traces that these newcomers left behind came in the form of concentrations of pits: 32 pit groups have been excavated thus far, each containing between 5 and 25 pits, with many other single or paired pits seen elsewhere. The pit groups themselves occur in five broader clusters that are spaced about 1km (0.6 miles) apart, spread right across the main excavated area. They occupy higher ground adjacent to shallow valleys, mainly on the sandy gravels but, for the first time, we find them on the drier Crag sands to the east as well. These clusters, sitting on dry sands above the wetter valley bottoms, are again interpreted as activity areas linked to open fields below. Some of the groups include potential storage pits – smaller and more ovoid than the Neolithic examples, but still with vertical sides and flat bases.
Another form of feature often associated with the Bronze Age are burnt mound/trough sites – enigmatic constructions typically interpreted as being linked to heating water. We have identified two such sites so far within the project area – one sitting at the edge of the clay upland, at the head of a valley on the Sizewell Link Road (C), and the other beside the deep, peat-filled central valley at the core of the site (D), with good potential for more to come. Each would have been placed to exploit a different type of summer pasture, with both the clay upland and the peaty valley holding water through the drier months. As for what the mounds were used for, upslope of both we have found flint-working areas rich in scrapers – activity areas linked to the hide-processing that we believe was taking place at the mound/trough sites.
Once again, this intensity of activity appears to have been short-lived, perhaps lasting little more than 200 years, before quietening down again dramatically. Early Bronze Age archaeology post-dating c.1900 BC is currently sparse, limited to three barrows (two holding cremation burials), a small pit group on the Crag sands, and a single settlement site (comprising the post-holes of a roundhouse, accompanied by pits) just off the glacial sediments of the diamicton. Intriguingly, the post-holes of this structure contained substantial quantities of burnt worked flint and fired clay. Mark Knight of the Cambridge Archaeological Unit reports comparable evidence from Bradley Fen near Peterborough, which might suggest that this was a deliberate practice, a pattern rather than a coincidence.
Moving into the Middle Bronze Age, evidence for this period manages to be both widespread and sparse. Fragments of field systems – the earliest kind of formal agricultural enclosures – line the edge of the diamicton, but we have only excavated one well-preserved complex. Covering 16ha (40 acres) at the southern end of the main area, this comprises upwards of 30 separate fields linked to a broad droveway leading north into the head of the wide, central valley. No field systems appear to extend on to the eastern Crag sands, with this activity instead keeping on or close to the more pasture-friendly soils of the diamicton. Trackways, mainly aligned west to east, descend towards the coast; such routes may have prehistoric origins, though they are near-impossible to date precisely. Notably, pit-digging – which provided such abundant evidence of earlier activity – virtually disappears during the Middle Bronze Age at Sizewell, as elsewhere, again possibly linked to a greater reliance on pastoral agriculture.
After nearly another millennium of relative quiet, however, pit-digging surges again in the Early Iron Age. Over 1,000 such features have been recorded across at least seven major scatters, with these pits no longer coming in the tight, horseshoe-patterned arrangements of the Early Neolithic and Beaker periods: they now come in swathes. From Late Bronze Age activity along the edge of the diamicton, this then spreads eastwards across the sands and gravels through the early Iron Age, and by the beginning of the Middle Iron Age it has reached the Crag sands. Just as expansive is the pottery assemblage for this period, which now represents one of the largest early Iron Age collections in the county, spanning c.900-300 BC. In contrast to the fleeting Neolithic and Beaker occupations, the Iron Age phase of apparently very similar activity endured for up to six centuries.
Encountering individuals
The Roman story is different again. It is not a tale of run-of-the-mill farmsteads, towns, and villas (though we have excavated parts of the edge of the small Roman town at Hacheston). Instead, the focus here was on the coast and on what the coast provided: salt, an integral part of the Roman economy, without which the empire would not have functioned.
By the 2nd or 3rd century AD, the sea had advanced significantly, perhaps rising as much as 3m (10ft), with tide-deposited soils and sediments entering the central valley by at least the Early Iron Age. Three salterns (salt-processing sites; E, F, and G) have been excavated so far, some of them containing extremely impressive industrial features. We have also identified the back edge of a possible fourth example (H), though it might represent some other kind of coastal activity, as this site holds more pottery in its hinterland than the others.
Even more intriguing is an area referred to as ‘the Hub’ (I), occupying a 1ha (2.5 acre) site beside a north–south road that runs some 2km (1.2 miles) to the west. It holds post-built and sunken-featured structures; a smithy; numerous latrine pits; coins; and large quantities of imported pottery including abundant Samian ware, but this doesn’t look like any ‘normal’ Roman site. We are working on the theory that it represents a seasonal workers’ encampment. Salt production was specialised, intensive work, probably undertaken by expert, potentially migrant labour, perhaps from continental Europe. The Hub was linked to the saltworks by a series of trackways across what may have been rough pasture. There are no signs of Roman activity in the gaps in between, with one exception. Halfway between the Hub and the salterns, alongside one of these trackways, were five small burial mounds (A). Could these be the graves of workers who never returned home? Unfortunately, bone does not survive well in these acidic sands, but a couple of graves produced teeth; isotope analysis might tell us where these people grew up.
Other than these remains and the Bronze Age and Roman barrows mentioned above, burials are relatively rare at Sizewell – that is, until we reach the Early Anglo-Saxon period. The OCA team have excavated two substantial community cemeteries of this date, both located at the heads of valleys on the Link Road route, which would have served the populations of what would ultimately become the parishes of Theberton and Middleton. The Theberton cemetery (J) is the earlier of the two and includes 12 tightly packed barrows and at least 50 flat graves. The mounds, which varied in diameter from 3m (10ft) to 12m (40ft), contained a mix of cremation and inhumation burials, and one had a closely spaced ring of fence posts inserted into its ditch. Some of the individuals within the barrows were of particularly high status, including a ‘warrior’ furnished with a sword, spear, bucket, bowl, and silver-rimmed drinking cup, and buried alongside a horse; and a cremation contained within a large, bossed urn and accompanied by a Coptic bronze bowl. These rich, almost ‘princely’ graves date to the early 6th century, while the flat graves that lie around them perhaps continue into the late 6th or early 7th century. The second cemetery, 3km (2 miles) to the north-west at Middleton (K), meanwhile, comprises over 100 graves, together with the remains of an enigmatic timber building. Measuring 9m by 6m (30ft by 20ft), this squat, rectangular structure has two pairs of large, central posts in the northern and southern walls and a slightly bowed southern frontage; we suggest it could have been a mortuary building or ‘chapel’.
Some 3km (2 miles) to the south lies the project’s largest Early Anglo-Saxon settlement (L), which was occupied from the late 5th/early 6th century until at least the early 8th century. There, we recorded nine sunken-featured buildings and at least 20 post-built structures, along with ovens, enclosures, and a well. This was, however, only one edge of a much larger spread of settlement that extended to the south-west, west, and north. Ipswich Ware appears in the pottery record before the settlement contracts westwards into Leiston, and from this we can estimate a date for what is perhaps the defining archaeological act of the post-Roman and medieval eras: the nucleation of Early Anglo-Saxon open settlements into the parish/village landscape in which we live today.
Adding to this picture, north of Leiston we found tantalising traces of a Middle to Late Anglo-Saxon estate centre spanning an area of up to 80ha (200 acres). Excavation along its margins has revealed enclosures, structures (including a possible roadside chapel; M), odd, sunken-featured buildings with ovens in their bases, and a coin hoard buried at the junction of two ditched enclosures (N). Dubbed ‘The Pasty’ because of its crimped lead wrappings, the hoard comprised 319 silver pennies and two cut halfpennies, making a total of 320d, or precisely 2 marks, and it was buried between 1042 and 1044.
Abbey lands
Further into the medieval period, the story of Sizewell’s archaeology is inseparable from the fortunes of Leiston Abbey, which was founded in 1183. Its initial site (O) lay on a marshy island, but after this landscape grew wetter, the community moved around 3km (2 miles) inland to a new spot (P) where the abbey remained until the Dissolution in 1537. This second site had been previously occupied by a medieval moated site, which coincides with the Late Anglo-Saxon estate centre that we partially excavated north of Leiston, and their histories were clearly intertwined. Although neither abbey site can be excavated, we can study how the associated land was used, particularly related to the community’s original location – and we also find the occasional artefact that links directly to abbey life, such as a beautiful Venetian glass pendant depicting Jesus on the Cross.
High medieval settlement in this landscape appears to be rare, with the exception of a roadside site (Q) to the south that probably lies beyond the core abbey land. We find agricultural working sites along the line of the earlier routeways, however, characterised by post- and cob-built structures, some with clay floors, and numerous ovens or kilns (many located within the corners of large, rectangular, sunken-featured buildings). Current interpretation suggests they may be crop-drying kilns, with wooden racking structures above them, perhaps for drying flax grown as a cash crop for the abbey. Flax and, to a lesser extent, hemp, used for the production of linen and hempen rope and cloth, are much under-reported in archaeology – we do not find cloth in the same ways that we find pottery, worked flints, cereals, and so on, so we do not discuss them as often as we should, but cloth production would have been a huge part of the agricultural regime and work-life of the populace from at least later prehistory until almost the present.
Excavation continues. New discoveries emerge constantly and our interpretations will also evolve – those above are not set. Yet already this project feels exceptional in a 40-year career: a unique opportunity to understand how people used their landscape, day by day, across six millennia. Who did what, where, when – and why? It is a privilege to be part of it.
All Images: Oxford Cotswold Archaeology
