CPAT logo
Cymraeg / English
Back Home
The Dyffryn Lane prehistoric ritual complex

Dyffryn Lane Henge Dig Diary, 2006


CPAT PHOTO 86-C-119 The Dyffryn Lane Henge Complex Project, directed by Dr Alex Gibson, was run run jointly by the Clwyd-Powys Archaeological Trust and the Department of Archaeological Sciences of the University of Bradford and was undertaken with grant aid from Cadw and other sources.

The fieldwork project ran from early July to the middle of August 2006. It focused on the investigation of the henge monument at the centre of the Dyffryn Lane prehistoric ritual complex - an important complex of monuments in the fields to either side of Dyffryn Lane, Berriew, in the Severn valley, about 4 miles south of Welshpool, Powys.

It aimed to find the excavation trenches dug in the mid 19th century to evaluate the preservation of the henge monument and the degree of agricultural erosion, to test and date the perceived stratigraphical sequence at the site, and to place the site in its chronological and ancient environmental setting.

Topographical and geophysical survey were undertaken on other monuments within the complex in order to elucidate their form and condition. The project also provided training in various field archaeology and excavation skills for students within the Department of Archaeological Sciences of the University of Bradford.

During the course of the work those invloved produced a day by day Dig Diary . . . . .

Monday 3rd July

Today sees the arrival of the Bradford University student workforce, and all of the equipment needed for the following weeks. Tomorrow (Tuesday), the archaeologists will be digging a trial trench to assess the depth of the topsoil. The reason for this is that mechanical diggers will be used to remove the topsoil from the excavation area (much quicker than with shovels!), and they need to know how deep it is to avoid damaging the archaeology with the digger bucket.

The Dig Diary Team from left, Charlotte, Jeff and Abi

Also starting early this week is the topographical survey. This involves close-interval contour plotting, which will evenutally produce a digital terrain model of the field showing the barrows and henge and any other earthwork features. This is one of many non-invasive methods archaeologists use to learn about sites, and is particularly useful for placing the site within the context of its surrounding area. The archaeologists will also be using geophysical survey, particularly resistivity, later in the project - check this site regularly over the coming weeks to find out more.

Right: Your intrepid CPAT dig-diarists, from left, Charlotte, Jeff and Abi

Friday 7th July

Well, what a busy week it's been on site. After a day of deliveries on Monday (equipment, sheds, the all-important porta-loos and students!) the work began in earnest on Tuesday. The topographical survey was started, with one of CPAT's supervising archaeologists Wendy Owen teaching the students. They surveyed the trench area before the digging started and then moved on to the area where the spoil will be dumped. On Wednesday they began filling in the area in between, and will eventually survey the entire field (more details of this at a later date). Another important job on Tuesday was to build the photography tower. This rather rickety-looking (but very safe!) scaffold structure will be used throughout the project to photograph the progress of the excavation. It is always very useful to have photos taken from a height, as you can see a larger area of the ground.

Focus On: Topsoiling

CPAT photo © 2155-006

Above: Bradford University students digging test pits to assess topsoil depth on Tuesday

Topsoil is the term given to the very top layer of soil in which grass and other vegetation grows. Topsoil depth can depend on many things, from underlying geology to what the ground is used for. A field that is regularly ploughed to grow crops will have a much thicker topsoil than that on top of a mountain, for example. Because we often don't know how deep the topsoil will be on any given archaeological site, it is usual to dig one or more test pits (a small area excavation, usually 1m square) to find out. This is also know as profiling the site. Once you know the profile of the site, a mechanical digger can be brought in to remove the rest of the topsoil. On Tuesday the students dug a series of five test pits along the length of what will become the excavation trench to assess the depth of the topsoil. They found several pieces of flint and some sherds of prehistoric pottery in the topsoil, which was very encouraging!

CPAT photo © 2155-016

Above: And topsoil stripping the easy way!

The mechanical digger moved in on Wednesday to remove the topsoil from the entire trench area, closely monitored by Ian Grant, CPAT supervising archaeologist, and several of the students. They found the top of a large stone beneath the topsoil, thought to be one of the stones mentioned by local 19th century antiquarian D. Phillips Lewis, which is presumed to have been part of a stone circle, so this was very exciting. One of the aims of the project is to find the trench dug by Lewis in 1857 to put his discoveries into context with the findings of our excavation. By the end of Friday, all of the topsoil had been stripped and the students had begun 'cleaning back', which basically involves trowelling the entire surface of the trench sytematically layer by layer looking for features and finds. So far, four large stones have been found in the top of the mound; as the trench gets deeper we will be able to tell if these are in situ or have been repositioned in the past. So far no diagnostic prehistoric finds have turned up, only more unworked flint and various modern items such as post-medieval pottery, iron nails and even a World War I button.

Visit the Dig Diary next week to see how they're getting on.

CPAT photo © 2155-029

CPAT photo © 2155-033

Friday 7th - what a difference three days makes! The students cleaning back (left) and the digger removing the last of the topsoil revealing the extent of the excavation area (right)

Friday 14th July

CPAT photo © 2155-050

Above: Holly with her barbed and tanged arrowhead

Things have moved on apace during the last week. As the students cleaned back the entire trench, a much broader picture of the site is coming to light. Now clearly visible is the outer ditch and bank which makes up the larger henge monument surrounding the mound. Within the alignment of the bank, an impressive collection of prehistoric pottery (including Peterborough Ware), initially found by Stephanie Lockwood, was discovered within a pit feature that may pre-date the henge bank itself. Another exciting discovery was made by Holly Crawford, who unearthed an Early Bronze Age barbed and tanged arrowhead from within the central mound. The site supervisor, Ian Grant, was very envious of such a find as it took him fifteen years of professional archaeology to find such an artefact!

CPAT photo © 2155-039

Above: Students cleaning around the possible stone circle

Further flints, including finely crafted blades, have also been discovered solely within the area of the mound. The trench in this area has been extended as we have still not found the trench dug by Lewis in the 19th century. This has led to the discovery of more large stones and as these appear evenly spaced, it has given further impetus to the suggestion that these are part of a stone circle rather than a kerb surrounding the mound. Only further investigation into the positioning of the stones will determine whether they pre-date the mound, and with the discovery of an infilled hole where a stone once stood, the students are eager to dig this out and perhaps reveal the nature of this relationship.

CPAT photo © 2155-051

Above: Dave (a.k.a. Dai Flint) with some of the flints he found

Student Story:

"With Dyffryn Lane henge being my first ever dig experience I wasn't sure what to expect when I first rolled up to the site early on Tuesday morning. Getting out of the car I had a quick scan around looking for the possible area we had come to excavate, and to be honest, my untrained eye could barely see anything remotely henge-like. When Alex (Gibson, site director) first pointed out the mound I have to admit it didn't seem like a tough task to face, I couldn't have been more wrong. Having been gently eased into the dig over the first couple of days I thought the three weeks I would be spending here would be a doddle, I'd hardly broke a sweat and my tan was coming along nicely. Then came the dreaded trowelling back... I never once thought I would be spending most of my time crawling in the mud on my hands and knees with the sun beating down on my now red raw back, neck and scalp!

As we come to the end of our second week we are still trowelling back and I have to say I think I'm getting used to it. My hands now look like leather and I've found a few good pieces of flint, which always spurs me on to find more and more. The henge is now starting to take shape and I think next week is going to be very, very interesting - when we actually get right into the archaeology. I can't wait."

David Chambers, 2nd year BSc Archaeology student, University of Bradford.

Some more pictures from week ending 14/07/06.

CPAT photo © 2159-032

CPAT photo © 2159-047

Above left: View from the tower showing the dark 'sweep' of the ditch (marked by ranging rods), with the edge of the outer bank shown clearly in paler soil. The current profile of the ditch can be seen where the diggers are standing at the far side of the trench.

Above right: Four of the stones buried within the mound. The one at bottom left appears to have fallen.

CPAT photo © 2159-052

CPAT photo © 2155-046

Above left: The filled in hole where a stone once stood (grey patch at left). This will be excavated by the students. Another stone can be seen at top right.

Above right: The large, presumed fallen stone, with Dave Greenwood cleaning back to another stone behind him.

Photo: Alex Gibson

CPAT photo © 2159-026

Above left: Students Dave Jones and Jema Bull cleaning around the Neolithic pottery within the pit.

Above right: The pit with most of the pottery removed and in finds trays.

Friday 21st July

CPAT photo © 2159-067

Above: The A Team: Back from left - Holly Crawford, Wendy Owen (CPAT supervisor), Rachel Stebbings, Jema Bull, Natasha Francis, Stephanie Lockwood and Dr Alex Gibson (Site Director); Front from left - Barney Hopcraft, Dave Greenwood, Dave Jones, Steven Crabb, Daniel Mosley, Dave Chambers, Neil Russell, Ian Grant (CPAT supervisor), Tim Davies

Today sees the departure of most of the Bradford students. They have all worked extremely hard but hopefully they enjoyed their time here on such an exceptional site. For most of them, this was their first dig, so I hope all the trowelling back hasn't put them off. The next group of students will be arriving on Monday, so new faces will be appearing on the Dig Diary.

A major problem that we have had since the dig began is the weather. It may seem wonderful to be digging in the sunshine, but it has been difficult to see any features in the baked ground surface and digging is very hard work. Though no-one wants to work in pouring rain, water does make the subtle colour changes of different soils stand out, so we have been watering the trench to clarify the location and extent of the features. It is amazing how many new features 'appear' when a site has had a good shower of rain, so we are all doing rain dances here in Welshpool. Some geophysicists came on site this week to start the resistivity survey, but they eventually had to stop as they were having difficulty getting the probes into the hard ground. It is hoped that conditions will improve enough over the coming weeks and they can get some good results.

CPAT photo © 2159-073

Right: The excavated stone hole with students Dave, Holly and Rachel

This week the students have been digging out the stone hole and when they reach the bottom we will hopefully have a better understanding of the relationship between the stones and the mound. A trench will eventually be opened up around two of the other stones so an even greater understanding of the sequencing should be obtained. An intriguing feature appeared when the mound was cleaned back - a narrow linear cut 40-50cm wide with a rounded end - but on excavation, it seems to be an animal burrow. In the outer ditch of the henge, another pit has been found close to that containing the Neolithic pottery, so hopefully permission will be granted to excavate this. It will be very exciting to see if more pottery comes out of this pit, but it may differ from the first as that lay beneath the outer bank, whereas this one is cut through the bank. A large section has been opened across the ditch. With luck it will be deep enough to get some interesting finds, but not so deep that we don't reach the bottom in the next three weeks!

CPAT photo © 2155-070

Away from the dig site several students have been cleaning up and processing some of the finds. The Peterborough Ware pottery has been carefully cleaned and looks wonderful, with the nail marks and other patterns clearly visible. From the same pit as the pottery came lots of burnt material and several pieces of plant matter including bits of twig and hazelnut shells. These have all been carefully washed and will be sent off for analysis and hopefully dating.

Left: Two pieces of the Peterborough Ware pottery from the pit feature.

CPAT photo © 2159-040

Above: Holly where she found the early Bronze Age arrowhead within the mound

Student Story:

"When I applied to take part in Alex's dig in Wales, I didn't know what to expect... like having to trowel back for days and days. But it's been worth it - we've found some very interesting features below the ploughed soil. On top of that, some of us have found pots and flint. The barbed and tanged flint arrowhead that I almost didn't find is one of them. It makes trowelling back all worthwhile! For my first dig I managed to find a complete arrowhead. Better than finding a body!

I have enjoyed myself immensely - making new friends and having a new experience. I'm looking forward to next week's work (now that trowelling back might be over), and if it's good, I might want to stay for more.

Not bad for a first dig!"

Holly Crawford, 2nd year BSc Archaeology student, University of Bradford (Holly wrote this piece a week ago but we couldn't fit it in then - ed)

CPAT photo © 2155-066

CPAT photo © 2159-061

Above left: Some of the burnt material from the pit feature

Above right: View from the mound out towards the ditch, including the stone hole (foreground), animal burrow (just behind) and ditch sections (background). The profile of the mound and ditch can be seen along the edge of the trench

Dr Alex Gibson, University of Bradford, Site Director

This was the last day for the first cohort of Bradford students and, as luck would have it, we found Phillips Lewis's trenches! More later.

This week has been spent planning the site, excavating the ditch, excavating the stonehole of the removed stone, washing finds and processing environmental samples. Each of the students has been given the opportunity to undertake many of these tasks as part of their training.

The ditch is proving to be about 5m wide. The edges were at first quite difficult to identify given the ill-sorted nature of the Severn Valley gravels but now that we have excavated about 20cm into the upper silts, the edges are becoming more apparent. The finds from this feature are still relatively modern (sherds of medieval pottery) so we may have a way to go yet before we reach prehistoric levels.

The stonehole was completely devoid of stone!! This was probably the site of a stone that was removed comparatively recently by the previous farmer and before the site was protected. An important find from the stonehole was a piece of thin tin foil, probably from a packet of tobacco or cigarettes, which clearly attests the modern date for the removal of the stone. Interestingly, the stonehole does not penetrate the underlying gravel and so it would appear that the stone was inserted into the existing mound. This suggests that the stone circle may be later than the mound.

Photo: Alex Gibson

The Neolithic pottery from the pit below the bank has been washed and cleaned. It is clear that this is middle Neolithic Impressed ware, also called Peterborough Ware, and dates to 3600-3000 BC. There are at least 3 different pots in the assemblage.

A large amount of charcoal was also recovered from the soil around the pots. This has been washed and sieved and now comes the laborious task of picking out all the modern root material. The charcoal will need to be studied by a specialist, but already it is apparent that there are some twigs and also fragments of hazelnut shells. These short-lived fragments will be used to provide radiocarbon dates.

At about 2pm on Thursday we saw something that we'd not seen in the previous 3 weeks - a cloud! This cloud grew until it actually became quite overcast. Colours returned to the bleached turf mound and there, faint but certainly visible, were two linear cuts through the mound. One runs east-west from the stone to the east of the stonehole and then runs into the section. The other runs NE from the centre of the mound to another stone in the NE arc. These agree with Phillips Lewis's description in every detail bar one: at less than 1m wide, they are not the 'broad' trenches that we were expecting.

Right: Congratulations to site assistant Dave Greenwood, who graduated this Friday with a 1st class honours degree in BSc Archaeology from the University of Bradford. Doesn't he scrub up well?

Wednesday 26th July

Dr Alex Gibson, University of Bradford, Site Director

Monday saw the arrival of the second tranche of students. Alex, and Ian were on site with Alex's wife and son (Jane and Ben) and some students who had arrived early. The day was spent taking down the photographic tower, clearing up the edges of the 1857 trenches and trying to define the edges of the henge ditch... not as easy as it sounds in the ill-sorted Severn gravels. Jane planned the area of the bank in preparation for a section through it.

Photo: Alex Gibson

On Tuesday, with everyone on site, we re-erected the photographic tower on the western side of the site where we've decided to situate our main section. Alex managed to 'cadge' a flight from local pilot Rob Jones. The henge was really showing well with greener vegetation growing in the ditch. The photograph supplements the survey and clearly shows the position of the trench in relation to the monument. Work continued on the main ditch, the antiquarian trenches and on processing environmental samples. We had our first visitors to site. Chris Musson and Toby Driver, having flown over the site while taking aerial photographs, decided to visit at ground level.

Left: The henge ditch showing as a dark grass mark with the excavation area.

Photo: Alex Gibson

Wednesday was a GOOD day. The north-eastern of the antiquarian trenches was finished and the stone proved to be much larger than it appeared on the surface. A little more work needs to be done, but it appears that the stone sits on the old ground surface (that is the prehistoric soil level). Unfortunately, Phillips Lewis had dug a large hole around the stone so no relationship between the stone and the mound survives. This important question will have to wait until later.

The ditch edges were finally found. It looks like it is about 6m wide... the dig team have started a sweep stake on how deep it might be!!

Right: 'First Dig Ben' (Alex's son) gets to grips with the 1857 trench while students Dave and Paul excavate the stone.

Friday 28th July

CPAT photo © 2155-077

Above: The view from the outer bank towards the mound

Since Wednesday, most efforts have been spent digging away at the ditch and ensuring that that all 'contamination' of the site from the antiquarian trenches is removed. The narrow feature that was initially thought to be an animal burrow (see entry for 21st July) has now been confirmed as one of Phillips Lewis's trenches, and actually extended out to incorporate another stone. With both antiquarian trenches fully excavated, work can begin on removing the upper mound material and hopefully ascertaining the relationship between the mound and the stones. A 3m strip starting at the top of the mound going all the way out towards the outer bank will be taken off.

The ditch is now approximately 1m deep and we appear to be nowhere near the bottom. Sherds of pottery from the ditch infill have shown that we have hit medieval or earlier levels, certainly pre 12th century, so there may be some way to go! Beneath the spread of bank material beyond the ditch there is a preserved prehistoric ground surface, associated with which are flecks of charcoal, a hearth and a further feature which remains to be interpreted.

Focus On: Topographical Survey

CPAT photo © 2155-022

Above: Stephanie Lockwood using the EDM, supervised by Wendy Owen of CPAT

While most of the dig team have been involved with the henge excavation, several of the students have been assisting with a topographical survey of the henge and surrounding area under the supervision of Wendy Owen, CPAT Site Supervisor.

The survey uses the latest digital equipment to record a series of spot heights across the area, based on a rough grid. The readings are taken using an Electronic Distance Meter (EDM), which uses a laser aimed at a prism on the survey staff to measure distances and record horizontal and vertical angles. The information recorded for each point is transmitted to a notebook computer running Penmap survey software to produce a plan of the site. The software can also provide a contour plan, by analyzing the spot height information and drawing lines (contours) joining points with the same value. These can be drawn at specified intervals which, in the case of the henge, are 0.1m apart.

Above: Results of the survey of the henge - Red = higher ground, blue = lower

The survey of the henge has taken readings every 3m to produce a detailed plan of the topography. The results clearly show the outer bank, ditch and internal mound. Within the same field there are also two round barrows, or burial mounds, which still survive as slight upstanding mounds, which will also be surveyed in detail. The rest of the field will be surveyed at a later date taking readings at a greater interval and the overall results will be used to produce a plan of the visible earthworks together with contour details.

Student Story:

CPAT photo © 2155-074

Above: 'Dai the Ditch'

Having excavated at the Lower Luggy Neolithic enclosure (500m or so NW of this site) during Easter 2005, I thought I knew what to expect at the Dyffryn Lane Henge. However, I think that the weather took everyone by surprise! The river gravel terraces are notoriously difficult to work on, but the bleaching effects of the dry sunny weather make it that more difficult, as changes in soil colour are more difficult to detect.

I am a mature student and twice the age of the main body of students here, however, having just graduated from the University of Bradford, and now partaking in my fourth excavation, I do have more experience and find myself assisting those with no experience in determining the difference between cunningly disguised mudstones and real ceramic and lithic artefacts.

At Lower Luggy I became known as Dai the Ditch, but for non-archaeological reasons, whereas this year the same nickname applies as I have been supervising the excavation of the henge ditch, which has been both daunting and good fun. Both teams of students have been very enthusiastic and hard working and have coped extremely well in the unrelenting heat and humidity.

Being an ex-member of the military my ditch team are working to a strict regime, and always tell me how lucky they are to be shifting the most earth and wheeling the most barrows full of spoil whilst the others get on with planning and drawing, however, all tasks during an excavation are equally important!

David Greenwood, post-graduate Archaeology student, a.k.a. Dai the Ditch.

Monday 31st July

Dr Alex Gibson, University of Bradford, Site Director

Photo: Alex Gibson

Above: Mark Harrison recording the hearth below the henge bank

Rain! Rain over the weekend greatly helped soften the concrete-hard earth and enhanced the hitherto bleached colour differences in the various soil deposits. A bright red patch of burnt clay under the henge bank in the northern part of the site produced some charcoal, and this will hopefully give us a radiocarbon date for the construction of the henge element of the site.

Excavation round the base of the standing stones now seems to confirm that the stones pre-date the central turf mound. However, there now seems to be more than one phase to the mound and this phasing now needs to be resolved.

Archaeologists are never satisfied. Having been praying for rain over the last few weeks, we now need an end to it - at least for a couple of days - and while we have no wish to return to the heat wave, a few dry, mud-free days will help sort things out.

Student Story:

CPAT Photo © 2155-104

Above: 'Shut-up-Dave' with 'Old Rusty' his favourite barrow

I have just finished the first week of my first archaeological dig and I was straight into trowelling back. It didn’t feel difficult at first and it seemed like we had done a lot until we stood up and turned round! Everyone seems to complain about trowelling back, but I enjoy it... it’s the barrowing that I dread!

I was pretty lucky midweek. I was emptying the antiquarian trench, finding flint flakes and amassing the best nicknames on site - Goth-Dave, Emo-Dave, Wise-Dave (I don’t remember this one!! - Alex, Dig Director) and Shut-up-Dave (I DO remember this one! - Alex).

In the first week the heat was unbearable. I was lucky not to be sunburnt, but the mattocking and shovelling made everyone feel exhausted. You think heat’s bad? Try rain! The weather broke over the weekend and it rained quite heavily on site today. The mud sticks to the trowel and it feels like you’re trowelling mud with mud.

Despite this, I’m finding it educational and a really fun ‘hands on’ experience. I just wish that having done a rain dance, there was such a thing as the sun dance. (There must be! After all there was the Sundance Kid - Alex).

Dave Errickson, 2nd year BSc Archaeology student.

Wednesday 2nd August

Dr Alex Gibson, University of Bradford, Site Director

Our wishes were granted. It stayed fair and a number of features have come to light. More work has been undertaken within the stone circle and we got down to the prehistoric land surface. This is now being removed in the hunt for datable features and artefacts.

It now looks as though the stone circle is earlier than the turf mound (but by how much?) and that the henge is later than the turf mound because there appears to be some up-cast from the henge ditch over the edges of the turf mound. But again, by how much? It is very likely that only radiocarbon dating will resolve this.

We still haven’t bottomed the henge ditch. At 1.8m deep at the moment, there are a few disappointed people... not because they had firm well-argued archaeological views but because they had less than 1.8m in the dig sweepstake!!

SAD NOTE - We heard today that Richard Avent from Cadw, and his teenage son died today in a diving accident while on holiday in Gozo. Richard is the husband of our Inspector of Ancient Monuments, Dr Sian Rees, who has been extremely supportive of the project. The entire dig team would like to send their sincere condolences to Sian and family. Our thoughts are with them at this very sad time.

Friday 4th August

CPAT Photo © 2155-117

Above: Flints recovered from the prehistoric land surface (core at bottom right)

Since Wednesday there have been some exciting developments. Excavation of the prehistoric land surface within the stone circle has resulted in the discovery of several flints. These are of fine quality, of a dark colour and include a core (a large piece from which flakes have been removed to make tools). Some of the flints have a white layer (the cortex) on their outer edges, suggesting they were originally recovered from an area of chalk geology, and imported to the site. Alex’s first thoughts are that the core is of Mesolithic date.

CPAT Photo © 2155-115

Above: Paul Cross, sweepstake winner!

The excavation of a section of the ditch has been completed and at 2.10m in depth it’s some ditch! By studying the sections it is possible to see the different coloured layers of soil, and how it has been washed, or deliberately pushed, back into the ditch over time. Paul Cross was the lucky winner of the ‘Ditch-depth Sweepstake’!

With permission from Cadw the team have begun to excavate the other half of the pit from which the Peterborough Ware was excavated (see entries for 14th and 21st July above). Further pieces of Neolithic pottery have already been found and it is hoped that more will be recovered as excavation progresses. Along with environmental remains this will hopefully provide a date after which the bank was constructed.

With the Open Day on Sunday fast approaching preparations are being made to welcome the public to site. Look out for signs on the A483 directing you down Dyffryn Lane and into the excavation field.

CPAT photo © 2155-109

CPAT photo © 2155-126

Above left: 'Old Rusty' and friends

Above right: The excavated ditch section, 2.10m deep

Friday 11th August

CPAT photo © 2159-124

Left: The B Team, stuck in a rut?: Back, l-r - Dr Alex Gibson (Site Director), Ian Grant (CPAT supervisor); Middle, l-r - Rachel Stebbings, Wendy Owen (CPAT supervisor), Rachael Clark, Hannah Measham, Lauren Hughes; Front, l-r - Mark Harrison, Dave Laurence, Edmund Kendall, Mark Errickson, Paul Cross, Dave Greenwood

We've reached the end of the dig! Six long, hard weeks of digging in the baking sunshine. It's been a successful excavation of one of the most intriguing archaeological sites in this area. The Dig Diary team would like to say a huge 'Thank You' to Alex, Ian, Wendy, Nigel, Dave, Rachel and all the diggers who gave us all the info we needed to write this diary (and posed for silly photos!). We've had lots of praise from fellow professionals and interested members of the public for the diary and we couldn't have done it without you. We are hoping to update the website when we get some post-excavation sampling results, such as the radiocarbon dates. We are not sure yet where we'll put this information, we may add it to the end of this diary or to a new page, so keep your eye out.

This week started with a successful Open Day on Sunday. It was very hot but windy and Alex and Ian were kept busy all day taking people round the site. The excavation continued throughout the Open Day and visitors were rewarded with some more middle Neolithic pottery from the existing 'Peterborough Ware' pit (now extended) and two smaller adjacent pits that were opened up that day. Now completely excavated, the large pit also contained some large stone fragments which appear to have been deliberately broken (some by fire) before deposition in the pit. A naturally rounded stone, presumably water-worn, was also found in the bottom. The two smaller pits contained mostly charcoal, but also hazelnut shells, all of which can hopefully be radiocarbon dated.

Photo: Alex Gibson

Above: Aerial-cam in action

Alex Gibson continues...
On Wednesday we had a very useful visitor to site. Adam Stanford from Aerial-cam arrived with a hydraulic monopod on which was mounted a digital camera. He took some high level photographs for us and we look forward to seeing the results. Today also resolved one of the stratigraphic problems that we had. The relationship of the stone circle to the turf mound had already been established. The stone circle is earlier. But by how much? We will not know for certain until the radiocarbon dates arrive but today we established that the pre-mound turfline runs right up to the stones. Not only that, but the stones had started to fall over before the mound was built. It looks like the stone circle was already fairly old before it was buried in the turf mound.

Can I have the radiocarbon dates now please??

The final recording started today and, once the plans and sections have been drawn, some extensive soil sampling will begin.

HAPPY BIRTHDAY to Shut-up Dave (Wednesday) and Rugby Dave (Thursday).

Photos from the Open Day

CPAT photo © 2159-131

CPAT photo © 2159-129

Above left: Visitors gather round to see the early Bronze Age arrowhead

Above right: Visitors watching the excavation of the pottery pits.

Focus On: Geophysical Survey

CPAT photo © 2159-053

Above: Claire Graham from Stratascan 'probing' with student Stephanie Lockwood

In the third week of the dig, some geophysicists from Stratascan came on site to carry out a resistivity survey of the two barrows and other features across the field from the henge. Resistivity measures the ability of electrical current to pass through soil. As resistivity is linked to moisture content, and therefore porosity, hard dense features such as rock will give a relatively high resistivity response, while features such as a ditch which retains moisture give a relatively low response. Remote probes are placed outside the survey area and in this instance, a hand-held meter containing twin probes 0.5m apart took readings at 1m intervals along 1m transects (so a 10m x 10m grid would produce 100 sampling points). Not surprisingly, our survey took two days!

Stratascan ©

Above: Results of resistivity survey (top of picture points north-west). Low resistance = lighter areas, high resistance = darker

The results have largely confirmed (and accurately located) features that had previously been identified from aerial photographs and earthworks. The two barrows show up very well, and the differing responses suggest two different types of barrow or varied construction methods. Though both may be ploughed out bowl barrows, with a large mound surrounded by a ditch, the northern may be a saucer barrow, with a low mound, and the southern a disc or bell barrow, with a small but high mound, which could explain the high resistance anomaly (the dark circle) in the centre of the barrow. Another explanation for this dark circle could be a burial within the mound, but without excavating the barrow we are unlikely to find out. What looks like a causeway (an entrance similar to that of the henge) can be seen in the ditch on the left hand side of the northern barrow. If this is the case, the barrow would be best described as a 'hengiform monument'. In addition to the long field boundaries of unknown date (the rather obvious straight-ish white lines on the plot), further intriguing linear anomalies occur in the results. At the top of the plot, a cut feature can be seen running parallel to the long boundary and joining the right-hand side of the northern barrow; also, a faint halo around the top of this barrow can just be seen, possibly indicating an earlier phase of this monument. In the very top left-hand corner of the plot, the corner of a curvilinear cut feature can be seen, which may represent the ditch of an enclosure. The thicker anomalies of low resistance (light-colouring) seen at top centre curving round and bottom sweeping up from below the barrow are thought to be paleochannels, the fossilised beds of old water courses. Though not strictly archaeological, these help us to build up a picture of the history and prehistory of the site.

More than anything else, the geophysical results confirm that the fascinating prehistoric remains of this area are not restricted to the henge. We are not sure how likely it is that any future archaeological work can take place within the field (not least because the entire field is a Scheduled Ancient Monument), but if so, we clearly now know where to start.

More photos from the last week of the dig

CPAT photo © 2159-165

CPAT photo © 2159-163

Above left: The partially excavated barrow and stone circle.

Above right: Close-up of two of the stones; the hole where the fallen one stood can be clearly seen at front.

Photo: Alex Gibson

Photo: Alex Gibson

Above left: The ‘Birthday Boys’ Rugby Dave (Laurence, left) and Shut-up Dave (Errickson, right).

Above right: The ‘mobile field laboratory’. Hi-tech drying facilities for charcoal samples.


Privacy and cookies