Three parallel features have been found coming westward out of Chawton Park Wood. Ref 1 summaries what is known. This southern feature is likely to be the original Roman Road, paying little heed to gradients across valleys, while the northern feature is a later upgrade with shallow gradients. Between them is some sort of water feature associated with a mill pond at the bottom of the valley, with the causeway of the southern feature providing the dam and probably housing the mill. This report describes the excavation on this southern feature, on the edge of Chawton Park Wood, marked S on the map in Ref 1.
The above Composite Section shows typical stratigraphy for this wood. Thin Top Soil, with 20-30cms of subsoil gradually getting redder into the clay natural. The estimated position of dark lines from air photographs are indicated by arrows, and a light line is between 80S-90S. The principal features found are two packed flint revetments at the edges of the Road, corresponding with the edges of the light line, clearly showing on the Composite Section.
Excavation approaching the revetment from the north found increasing flint in Trench 3B, becoming pretty well packed flint between 81S-83S. It is also set deep into the clay. The southern revetment is similar between 89S-91S, but appears to be not so substantial or go so deep into the clay. The land is falling slightly to the north, and one would expect the downhill revetment to be bigger. Revetments are found on Roman Roads, and are designed to keep the metalling together. These Roads are likely to be Centuriation or estate Roads (Ref 2), and we have found that their metalling is crushed flint, probably laid thinly but frequently. This material does not show up in section, and is likely to be moved around by roots and frost action (Ref 4). We have developed ways of detecting it through counting the crushed flint found at intervals, and recording it with its depth.
Crushed Flint
The graph below the Composite Section shows the volume of Crushed Flint for each Trench. Clearly the volume is higher between the revetments than outside them, and far higher in Trench 5B. It generally occurs in the subsoil and at the top of the clay layer. That in Trench 4B is higher than Trenches outside the revetments – but not by a large margin. This may however be a correct result. It can be seen from the Composite Section that a large amount of flint shows in section in Trench 4B – so a substantial amount of the metalling here may be large flints next to the revetment. Further more the flint count for Trench 4B records 44 large crushed flints (the only Trench to do so). We are considering changing our arrangements by weighing rather than counting the crushed flint. One large crushed flint may be equivalent to 20 small ones - these features could largely close the gap between Trenches 4B & 5B. The conclusion is the Road was mainly metalled by crushed flint between the revetments.
Side Ditches
The air photo shows the Road as a light line bounded by dark lines coming across the fields from the west (Ref 1). The dark lines can be expected to be ditches. Through Chawton Park Wood to the east the air photo mainly shows a thin light line – which may be the larger revetment. The arrows above the Composite Section estimate where the dark lines are at the edge of the wood. However we did not find the usual evidence for side ditches in this excavation, with the section photos showing re-cut and silt lines.
There appeared to be a deep cut into the clay with a fill of different material in the western part of Trench 2B from 74S-76S. The profile of the Western Face is shown below the Composite Section for the East Face (though the depths are correct). This formed a complex structure – but has to be ruled out as a Roman Road ditch. In the western part of the Trench a green sandy material not seen elsewhere on this site with no bottom found was sealed by clay, or by Top Soil alone in the north of the Trench. There is no subsoil which serves to date the feature to around the Medieval period or later. The green sand, marked G on the Composite Section, did have silt lines, and was cut into to a considerable depth with a fill material marked as F. The bulk of this was yellow/red sandy clay which did not have silt lines. A smaller part as yellow brown sandy clay at the bottom of the cut into the green sand did have silt lines at a different angle to those in the green sand. A worked flint was found, shown by the arrow. The whole of this green sand had been up at some time. The interpretation is that this was a working pit, probably for the green sandy material which may occur here naturally, which was back filled possibly when these fields were formed out of Chawtoon Park Wood. Our Trench happened to go through near an edge of it.
There is a small depression in the clay surface from 75S to 78S – possibly associated with the Dark Line Arrow. But no cut-lines or silt lines seen on section photos, nor indications of any different fill.
There is a similar depression in the clay surface associated with the southern Dark Line Arrow between 94S-96S, though here there is a mark in the clay going down to the Trench bottom which is shown on the Composite Section for Trench 7B. There is also some buried Top Soil associate with it, and what was though to be a post hole in the clay but under the subsoil surface. A similar arrangement is visible on the West Face section photos – thought this face does not go deep into the clay showing the same lines. Different materials were reported by trowellers in this region, but none appeared to become a consistent feature. Possibly one set of cut lines visible on both faces, but no re-cut or silt lines show.
The side ditches showed up well in Magnetometary in the fields up to the edge of Chawton Park Wood (Ref 3), but were not confirmed in the wood to the east of the excavation in student exercises. This, with the air photo evidence, suggest the ditches fade out in this region. Either of these two depressions in the clay might represent the end of the ditches, where they they were shallow, and they may not have bothered to clean them out and re-cut them.
Interpretation
We have found a Roman Road with substantial revetments at its edges, between which was mainly crushed flint metalling. This is part of a three parallel feature system, probably being the first road, later replaced by the northern parallel feature as an upgrade. It may have been brought back into use with the construction of the central feature as some sort of water system. It may also be the start of a Centuriation Road – but its course westward is still to be determined.
Acknowledgements
Thanks are due to Mr John Cray for permission to excavate on his land, and to the 130 man days contributed by the diggers. Richard WhaleyTo print a full 1:20 Composite Section Click here for full size Composite Section then check your margins 7mm and set to Landscape [File - Print Set-up - Landscape, Margins 7mm, File - Print..]. After printing reset to default margins and Portrait.
REFERENCES
1. Southern parallel featue in Chawton Park Wood, NEHHAS FAB e News 10 Winter 2014 -15 http://www.nehhas.org.uk/rd13-14.htm
2. Note on Centuriation, NEHHAS NL No.91 Spring 2004, Journal 3 No.12 2007
3. Magnetometary of the Southern Parallel Feature, NEHHAS FAB e News 7 Summer 2013
http://www.nehhas.org.uk/rd13mag.htm
4. Flints on the Roman Road, NEHHAS Journal 3, No. 11a, 2015