Current Archaeology 172 - Special issue on Wetlands |
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Excavating the Sweet Track,
in Somerset. As the remains are so fragile, they can only be excavated
by suspending the excavators on planks, above the wooden remains,
which have been reduced to the consistency of butter.
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Current Archaeology 172 was published in February 2001
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Wetland archaeology has one big advantage over dryland archaeology: preservation. A whole range of material - including most notably wood - is preserved that is not found in dryland sites. Over the past 20 years, English Heritage has conducted a massive Wetland Project now coming to an end: what has come out of all this work? Current Archaeology was invited to do this special "Wetland" issue to mark the completion of this work. The work was divided into four areas: the Somerset Levels, the East Anglian Fens, the North West, and Humberside. |
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The Somerset Levels
Here the valley of the River Brue (and others) is only just above sea level, and is still liable to flooding - see photo left. In later prehistory, peat began to form, burying the sedges and reeds which formed the peat, and preserving the trackways that early man constructed across them. And since the water was anaerobic (did not permit air to pass through) any wooden artefacts were preserved. This were the site of the discovery in the late 19th century of the famous Iron Age 'Lake Villages', first Glastonbury, then the two adjacent villages at Meare, which still remain the the best preserved Iron Age villages yet discovered in this country.
He found that buried in the peat were numerous trackways, mostly of the Neolithic and Bronze Ages,where hurdles had been laid down leading across the rising peat from the high land on either side of the valley to the low islands in the middle of the valley. Here we see one of the trackways known as the Eclipse track, made of hurdles, and dated to around 1800 BC.
This was built in the winter or early spring of 3807 or 3806 BC - tree-ring dating enables us to give this very precise dating. This makes it the earliest of all these timber trackways discovered in northern Europe - indeed it has been claimed to be the oldest road in the world. This is very different in style from the later hurdle trackways, such as the one shown above. It was narrower, but rather more sophisticated, with an elaborate system of crossed posts enabling the track to be constructed above the level of the rising waters, as this reconstruction painting by Edward Martelmans shows. The track was discovered by the peat diggers, and part of it was inevitably destroyed. However the peat digging has now been stopped, so the rest of the trackway still remains, preserved in the peat. However the peat is drying out, and the trackway will crumble away unless it is kept wet. Thus a sprinkler system has been installed along its remaining length to keep it wet. If the drainage of our wetlands continues, it will only be by methods such as this that sites can be preserved. Click here for the Peat Moors Centre museum
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The
Wetlands Project began in the Somerset levels, near Glastonbury.
However
the peat that formed in the valleys was being cut away for use
as garden fertiliser, so in the 1970s, John Coles, Professor of
Prehistory at Cambridge University, began investigating these
peat cuttings.
The
earliest of the trackways discovered so far is the Sweet Track.
The Fenlands
English Heritage launched a massive field walking survey, and for six years David Hall and his team walked over 200,000 hectares of land, discovering over 2000 sites, of which 41 were test-excavated. The big surprise was the number of Iron Age sites; the Romans were not the first to settle in the area. Among the more spectacular sites were the salterns, salt working establishments where salt was extracted from the sea and traded inland. These began in the Iron Age and by the late Roman period some were on an almost industrial scale. The photographs show work in progress at Middleton where one of a number of hearths on which salt water (brine) was boiled to extract the salt is being drawn . For a well-known Fenland site see Flag Fen. |
The
biggest area of wetlands in England is the Fens, the region around
the Wash in Lincolnshire, Cambridgeshire and Norfolk. Drainage
began in the Roman period and has been going on apace from the
17th century onwards, until today it is almost entirely dry land.
Is there anything left?
The North West
The most famous is Lindow Moss in Cheshire from which two famous bog bodies were extracted in the 1980s (now in the British Museum). A more recent spectacular discovery was that of the Solway cow (above) which was found in the course of commercial peat extraction in the Solway Moss in Cumbria. Here the head of a cow was discovered complete with its hair, and radiocarbon dated to around 800 AD. Only the head was recovered; was this some form of ritual sacrifice? |
The
project was then extended to the northwest of England. Here
the problems were very different. Instead of huge flat expanses,
there were numerous smaller bogs or mires. These were of two
types: there were the valley mires, many of them essentially
extensions of the Lake District where peat had built up in valleys
that might otherwise have held lakes; then there were the larger
raised mires where the peat had grown up mainly through the
nourishment of rainfall. There are a number of these both in
Cumberland and in Cheshire.
The Humber Wetlands - and Sutton Common The
final area to be investigated was the basin of the River Humber.
At the end of the last ice age , around 9,000 BC, the melting
ice formed a large but short-lived lake named Lake Humber, stretching
from Hull across nearly to Doncaster, and up to York (the white
area to the left of the plan). In the following millennia the
sea level rose, and the Humber estuary became tidal, and the former
Lake Humber became a very extensive peatland.
Fortunately however the site has been saved. Ian Carstairs, a local conservationist, who has set up the Carstairs Conservation Trust, was persuaded to acquire the site, with funding from English Heritage, the Heritage Lottery Fund, and others. The drains that were draining the land have now been blocked up, a re-wetting scheme has been introduced and the archaeology will - hopefully - be preserved. The community and local schools have been involved, and there are plans for further excavation. Click here for an early English Heritage report, and the Hull University Wetlands Project |
The
major site for preservation has been at Sutton Common (8 on
plan above, at extreme left, and see air photo, right, taken
when the land was still being ploughed, and where one of the
two Iron Age enclosures stands out as a cropmark). This was
the site of an early Iron Age marsh fort, that was excavated
by Sheffield University from 1987 - 93. However the land was
being drained, and partly ploughed and the wood that was preserved
was in danger of rotting away.
Ramsar How
are we to preserve the dramatic archaeological remains hidden in
our wetlands? By ourselves, archaeologists are unlikely to have
sufficient political clout to do much preservation. We are far more
likely to be successful if we join other interests, notably wild
life and bird lovers.
In particular we need to look at the 'Ramsar' Convention on Wetlands. This was established at a conference held at Ramsar in Iran in 1971, and now there are numerous 'Ramsar sites' all over the world where wetlands are preserved - the equivalent of World Heritage Sites. Unfortunately the Ramsar Convention focusses on safe-guarding the natural environment of wetlands and their biodiversity. Archaeology is not directly included in the convention but archaeologists are working hard to ensure that when information sheets are drawn up for for Ramsar sites, archaeological interests are included. Further Information The main society concerned with wetlands - WARP, the Wetland Archaeological Research Project, was set up by John and Bryony Coles and based at Exeter University where Bryony Coles is Professor of Archaeology. |
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Created: February 2001