SOUTHERN PARALLEL FEATURE IN CHAWTON PARK WOOD

This area is under investigation at the time of writing. This latest report summaries the current findings and problems

In excavating the Roman Road on the western edge of Chawton Park Wood three parallel features have been found. OS map error has resulted in inaccurate plans if the features are added to OS maps, so we are making our own maps from Ref 1 Air Photos. This region is also likely to be the start of a Roman Centuriation estate (Ref 2), but at present we do not know which of these three features forms the Limites or estate road and boundary - which has been established some 2 miles to the west on towards Winchester. Understanding these three features is therefore important. This report charts where the southern feature goes eastwards.

Above is the Air Photo Map from Ref 3. It can be compared with the OS map from Ref 4. Excavations have been carried out on the western edge of Chawton Park Wood, marked S above. The southern feature has been partly excavated, and is a 24' road of crushed flint but with quite substantial packed flint revetments at its sides. The air photo lines from the west on Ref 1 photo are a light line bounded by dark lines. So far only 1 ditch has been found, associated with the north dark line.

This route was originally thought to be the Roman Road we were looking for, but on preparing the Survey Map it seemed it was unlikely to connect with large remains found around Stancomb (Ref 5). It is now realised this may be due to the OS Map error, but searches for other routes was conducted at that time.

At that time a binocular terrace was seen in Chawton Park Wood, the Cut Back of which is shown as the four light centred triangles. The Build-up ran where the dark lines are. A bump in the track which runs across the line (approximately where the cleared area is on the above Air Photo Map) was thought to be on the line. But in the current exercise, using air photos to plot known features this appears not to be the case.

                                         Line

- - N - S / / ------------- / - -

The above diagram illustrates the ground surface in the region of the bump, and the line of the Southern parallel feature runs above it. It may be that the Cut-back of the bump is actually the Build-up for the Southern parallel road - which is the biggest part of the bump feature. There is also the issue of the flows of soil down the slope here - which could be appreciable since Roman times. Soils near the ground surface will flow faster than soils near the bedrock, so the stratigraphy will be distorted. In all we cannot take this bump as the evidence it was previously given.

Air Photo Light Line

The cleared area on the above air Photo Map now has young trees and is very over grown. No ground evidence can be found. However the Ref 6 air photo gives a thin light line carrying on past the bump in the track, down the valley and up the north valley side [view obliquely into light]. It is present on the Ref 1 air photo in part of the cleared area. This thin line is likely to be due to one of the packed flint revetments found in the excavation. This light line is shown on the above Air Photo Map, and the one below.

This line crosses the E - W track visible on both Air Photo Maps, and is the bottom of the valley (eastern edge of above Air Photo Map). In 2003 a path followed this line up the N valley side, which was very steep, and we deduced too steep for a Roman Road. In 2014 this steep climb was not there, a reasonable gradient terrace takes the path diagonally up the N valley side. The conclusion is that this is an alteration since 2003, with much of the visible terrace being recent, to provide a convenient entry into the woodland. In which case the steep ascent we surveyed in 2003 is likely to have been the shoulders of a causeway across the valley. A tongue of land on the other side of the valley may also represent it.

Interpretation

It is expected that there would have been a causeway here, for causeways over valleys have been identified on this Road between Farnham and Bentley on a stretch considered to be a first Road (with later upgrade to have gentle gradients - Ref 7). Across valleys they get washed away, but shoulders - remains of the original causeway - may be found on the valley sides. Furthermore, although they may not be visible in the valley bottoms, soils are likely to be increased considerably in thickness by the washout - seen in Ref 7. This increased soil thickness (which in woods is generally thin) is likely to affect tree growth - which with the shoulders can produce avenues of trees visible on air photos (not necessarily visible in the wood), and provide evidence for the causeway and Roman Road.

There is some evidence for an avenue of trees going part way up the north side of the valley on Ref 1 air photo below [view obliquely into desk light, weak magnifier]. From this, and the height of the original climb, it is deduced that this was likely to be an unusually large causeway - larger than one needed to make a reasonable gradient and keep the Road off the wet valley bottom. On the limited evidence available, this may help provide an interpretation for the central parallel feature - a 60 Roman foot wide ditch cut into the clay with running lanes on its edges (Ref 8). The interpretation was that this ditch may be to collect water, possibly for something like a saw mill, and the running lanes suggested something like a canal - especially in rainy conditions when logs could be floated or hauled on the slippery clay. Recent work on possible Roman dew ponds (Ref 9) indicates they may have enlarged on the prime source of water (surface water retained by natural layers such as clay) by a system of ditches, especially ditches of a Roman Road. The natural in Chawton Park Wood area is clay. This central parallel feature may collect water from a wide area from the summit of the downs and down the valley - to the large causeway for the third parallel feature - which acted as a dam for a mill pond. Here, within the causeway may have been a saw or other type of mills. Transport of products to and from such mills could have been made along the Roman Road forming the southern parallel feature.

A thin light line is also visible on the Ref 1 air photo below, through the avenue of trees, to the strip of wood between the fields (above the label Air Photo Light Lines on the Air Photo Map below) [view into daylight weak magnifier]. Virtually no ground evidence can be seen. Ref 10 map indicates a track snakes around the line, of which some evidence can be seen - but none of Roman engineering. In the strip of wood between fields (the southern field is now wood) is a steep valley - no shoulders of a causeway can be found on this valley sides. The line runs through the next field/wood boundary - which is another steep valley. Here, on the western valley side, is a 30' of a low shoulder of a causeway, with a characteristic rounded end near the bottom of the valley - which is the track leading into the field visible on the Air Photo Map below. The shoulder is below the letter C. Nothing can be seen into the next wood strip - but the ground is reasonably level and engineering would not be visible especially in the woods.

Field of excavation

The line emerges from the wood boundary into the field of excavation, the site in the copse marked S. This route previously published is shown as a dashed line (Ref 10). The excavation found a substantial packed flint roadway between ditches 60 Roman feet apart (Ref 11). This line goes on to the Zig Zag, which also shows a substantial flint construction (Ref 12), and is also shown on the first Air Photo Map above. The second limb of the Zig Zag becomes the Northern Parallel Feature. This route was found because two dark lines were seen on the computer screen of Ref 6 air photo coming out of the kink in the wood and leading to the copse.

The line of the Southern Parallel Feature enters this field with weak and thin dark lines on Ref 1 & 6 air photos. For Ref 1 photo view into sunlight obliquely. Ref 6 photo shows a disturbance over half the field from the south boundary with dark edges 50' - 60' apart [70% Contrast obliquely into desk light with powerful magnifier]. On Ref 1 air photo, 500' from entering the wood at the east of the Air Photo Map is a light line with dark edges 30' apart for 250' [oblique into desk light, weak magnifier]. No ground evidence can be seen in these fields.

The line then goes into Ackender Wood, where an Avenue of Tress follows it on Ref 1 Air Photo [Oblique into Desk Light]. This appears to go to the same point that an Avenue of Trees starts on the route to the Zig Zag. This was reckoned to be the end of short alignment of the modern track shown on the Survey Map, Ref 10. This track is reckoned to be the Roman Road climbing up from Alton and is shown as such up to near Point A. As can be seen from Ref 10 this track is composed of short straight alignments. It was visited during this current survey and found that it is keeping accurately to the edge of the escarpment where the land falls away to the N and NW. All along here it shows the characteristic profile of a Mixed Terrace:

                                                                                 -
                                                -
N                                    -                      S
                                   /                                    
                                 /                                                                               
                    -------------
                  /
        -                
   -
There is a Build-up where the land falls away with a ditch below it, and a Cut-back with a ditch at its base, with a level way about 20' wide. The Cut-back looks as if it has been tidied up in modern times, and the ditches may have been re-dug - but its unlikely anyone but the Romans would have constructed such a terrace for such a distance - and keeping to the edge of an escarpment was Roman practice. This stretch to where the two Avenues of Trees meet should be taken as the Roman route. The Mixed Terrace construction is not seen west of this point.

Conclusion

This southern parallel feature has the hall-marks of a first road, as has been found between Holt Pound and Bentley (Refs 7 & 13). That is to say it goes straight over difficult country without much regard for gradient, except for providing causeways across valleys. Having climbed up to Ackender Wood from Alton, our Road swings back onto the 28 degrees N of Grid E direction, having to cross two steep valleys, and the main E - W valley in Chawton Park Wood with little engineering visible. A reason for this was found in the excavation of the Centuration Cross Road, where it was found that a first road was laid directly on the sloping ground (Ref 14) (later an Agger Terrace was constructed over it). A Road laid directly on the sloping ground will not show much engineering, but may show air photo evidence from the stonework - as is the case with this southern parallel feature.

Clearly, as with the other first roads mentioned there was a later up-grade - which is the one we found shown dashed on the Air Photo Map below. This is a more substantial construction as found in the excavation, and it takes a line to cross above the two steep valleys - to a substantially constructed Zig - Zag to bring the Road to the bottom of the valley. Only here does the Road swing back onto the 28 degree alignment - to become the Northern Parallel Feature. Though now it is a lesser construction of crushed flint but between two large ditches.

Probably later still the big 60' wide ditch with running lanes was constructed, which we suggest may be a Roman water feature, which may have brought back into use the Southern Parallel Road as a dam for a mill pond and to house a mill within it - plus transporting products to and from it. This southern road leaves more trace going westward, and possibly was up-graded at this time. It is not understood why the Northern Parallel Road becomes just a crushed flint construction west of the Zig - Zag - but it is thought there was a connection of the wide ditch and the Zig - Zag (Ref 4) - and we still have to trace the two parallel Roads west of the first Air Photo Map above.

Principal Surveyors

Donald Ashdown, Richard Whaley

Map Caption Air Photo Map made from Ref 1 Air Photo from Chawton Park Wood to Ackender Wood (NE of the Photo). The above Air Photo Map is reduced in size. To print a full size 6" : 1 Mile map Click here for full size Map then check your margins 19mm and set to Landscape [File - Print Set-up - Landscape, Margins 19mm, File - Print..]. After printing reset to default margins and Portrait.

REFERENCES
This Report was first published in FAB e News 10, Winter 2014 - 15

1. RAF air photo survey 1947 -9, scaled to 6" : 1 mile by OS, Hants Sheet 41/63 NE
2. Note on Centuriation, NEHHAS Journal 3 No.10, 2007
3. Richard Whaley, Chawton Park Wood Air Photo Map, NEHHAS FAB e News 4 Spring 2012 http://www.nehhas.org.uk/rd11-12.htm
4. Chawton Park Wood Zig Zag starts the Centuriation, FAB e News 3, Autumn 2011 http://www.nehhas.org.uk/rd10-11.htm
5. Centuriation west of Four Marks, NEHHAS Journal 3 No13, 2007
6. www.multimap.com 2000, gettamapping
7 Avenues & Causeways, NEHHAS Journal 3 No 6a&b
8. FAB e News No. 3 Autumn 2011 http://www.nehhas.org.uk/rd10.htm
9. Did the Romans have advanced dew ponds? FAB e News 8 Autumn 2013 http://www.nehhas.org.uk/sf12.htm
10 Alton to Chawton Park Wood, NEHHAS Jn 3 No. 11, 2007
11 Packed flint foundations, NEHHAS NL 104, Autumn 2007
12 Chawton Park Wood Zig Zag, NEHHAS Jn 3 No. 11c. http://www.nehhas.org.uk/cpwzigj.htm
13 Wrecclesham to Holt Pound Inclosure, NEHHAS Journal 3 No 5
14 NEHHAS NL 98 Spring 2006, Jn 3 No. 13a forthcoming