The Lost Roman Road From Chichester To Arundel
Analysis of lidar and aerial photography leads to the rediscovery of a long-speculated route of a Roman Road.
The success of the Roman Empire was founded on its network of trunk and secondary roads linking centres of military or commercial importance. Chichester (Noviomagus Reginorum) on the south coast was an important early settlement in Roman Britain, and developed into an important town and gateway port.
A number of arterial roads headed inland and along the coast. Four of these have been identified, but the course of the road east along the coastal plain has remained elusive.
Recent aerial survey by Historic England for the Secrets of the High Woods Project (working in partnership with the South Downs National Park) has now firmly identified the remains of this Roman road, the existence of which has long been a subject for speculation. The discovery has depended on a combination of aerial photography and lidar (airborne laser scanning) data; the latter technique’s great strength is its potential to reveal sites in heavily-wooded areas.
Roman roads were expertly surveyed and engineered, taking the shortest possible route the terrain allowed. Even in the provinces, roads were frequently solidly constructed, featuring a cambered and metalled causeway known as an agger, typically 4.5‒7m (and occasionally up to 10m) wide, and flanked by side ditches which provided drainage as well as being a source of the material used to build the road (Margary 1965, 15). The quality of their construction has ensured the survival of many stretches of Roman road to the present day.
Ivan Margary was one of the 20th century’s leading authorities on Roman roads.
As well as undertaking extensive research of his own, Margary also generously funded excavation and publication by others; and he secured the preservation of the Roman palace of Fishbourne.
His Roman Roads in Britain, first published in 1955, was the first definitive catalogue of all the major and minor Roman roads throughout the country. The maps it contained showed surviving, inferred and conjectured routes, each of which was allocated a unique number, now generally referred to as a ‘Margary number’.
Some of these routes were based on earthwork remains or alignments of current roads and boundaries, but others were more speculative.
Stane Street (Margary 15), was an early military road linking Noviomagus and Londinium (Manley 2002, 138), and probably the most important road for the Roman town of Noviomagus Reginorum. It sliced a north-eastern course through the South Downs. A second road (Margary 155) went north to Silchester (Calleva), while a third (Margary 421) headed west along the coastal strip towards Bitterne (Clausentum), on the upper tidal reach of the River Itchen. Finally, a short spur road (Margary 156) headed due south from Chichester to the coast (Margary 1955, 29‒30).
Logically, as Margary speculated in the late 1940s, a fifth road should run eastward along the coastal plain in the direction of Brighton, via Arundel (Margary 1947, 141). He investigated a number of potential routes for this, looking for possibilities that avoided both the hills to the north and the wetter ground to the south (ibid, 143‒4). Margary discounted one suggested route, which followed the line of the modern road running eastwards out of Chichester towards Oving, because although its first couple of miles (to Shopwyke) were straight, it then dwindled into winding footpaths.
His second and preferred route, though not entirely straight, branched east-north-east off Stane Street at Maudlin, to the east at Westhampnett. From here, Margary believed, it followed the course of the Old Arundel Road, now superseded by the A27.
At Crocker Hill, the Arundel road dog-legs to the south before returning to a roughly east-west course. However, this is a result of the road being diverted around Aldingbourne House and its park in the late 18th or early 19th century. Margary suggested the original course was indicated by a line of trees that crossed the park. He thought the route then continued eastwards via Alvisford, crossed the small, steep-sided valley of Binsted Brook at Binsted Brook Crossing, and proceeded on to Arundel via the old road that ran between Arundel and Torrington Common (Margary 1947, 161‒3).
This course was published as a confirmed route of the western section of the road heading eastwards from Chichester in the direction of Brighton (Margary 153) in Roman Roads in Britain (Margary 1955, 68), remaining unchanged.
The evidence discovered
During the recent Historic England survey for the South Downs National Park, significant sections of the road’s agger and side ditches were seen as earthworks and cropmarks on aerial photographs and 0.25m resolution lidar data. Traces of the road were identified over 8km of the total 15km distance between Chichester and Arundel.
The western end of the road is masked by modern development, but it is likely (as suspected by Margary) that it followed the course of Stane Street to a point north of East Hampnett, before branching off along what became the Old Arundel Road. This particular stretch is still fossilised as the surviving portion of the Old Arundel Road, which meets the new A27 as it sweeps in from the south-west between Boxgrove and Tangmere.
At Crocker Hill, the Old Arundel Road originally curved slightly to the east-north-east, but its Roman predecessor can clearly be seen, keeping its true east-west alignment as it crosses the park of Aldingbourne House as a slight linear embankment. Further sections of the agger continue eastwards, maintaining a straight course. With the exception of one section, where the remains of the parallel side ditches can only be seen as cropmarks on aerial photographs, all other traces of the road survive as slight earthworks. These appear to have gone unnoticed until now.
The longest stretch of the road is recorded on lidar images, and shows a raised causeway through the eastern end of Paine’s Wood, where it is now followed by the course of a woodland track. At the eastern edge of the woods, the route again meets the Old Arundel Road, which follows the presumed alignment of this Roman road into the outskirts of Arundel itself.
Whether by accident or design, for much of its course the road closely follows a band of marine gravel and cobbles, remnants of a Quaternary raised beach deposit. Gravels quarried from this same marine deposit were used in the construction of Stane Street to the north (J Kenny, pers comm), and it is likely that the Chichester to Arundel road also exploited this source of aggregates. Extractive pits detected by lidar adjacent to the road east of Crocker Hill may represent contemporary quarrying for road construction or maintenance purposes.
The discovery of the road is important, putting into context the Roman-era sites along its route. It is a small but significant addition to our knowledge of Roman Britain. It is also immensely satisfying to be able to confirm Ivan Margary’s theory through methods of remote sensing that would have been unimaginable sixty years ago.
Investigator, Aerial Investigation and Mapping section of Historic England’s Historic Places Investigation Team.
Fiona has worked for the organisation and its predecessors since 1992, trained as an air photograph interpreter, and subsequently worked as an aerial investigator. She has been involved in a number of major National Mapping Programme projects. Fiona has particular interests in 20th-century military archaeology, and in the contribution aerial archaeology can make to understanding historic landscapes and the evidence for the continuity of human activity through time.
Historic England 2018 Using Airborne Lidar in Archaeological Survey: The Light Fantastic
Carpenter, E Small, F Truscoe, K and Royall, C 2016 South Downs National Park: The High Woods from Above NMP. Historic England Research Report Series 14‒2016.
Manley, J 2002 AD43: The Roman Invasion of Britain: A Reassessment. Stroud: Tempus
Margary, I 1947 ‘The Chichester to Brighton roman road’. Sussex Notes and Queries; 11, 141‒63.
Margary, I 1955 Roman Roads in Britain: Vol I, South of the Foss Way–Bristol Channel. London: Phoenix House
Margary, I 1965 Roman Ways in the Weald. London: Phoenix House
Margary, I 1973 Roman Roads in Britain, rev edn. Trowbridge: Redwood Press
This page was first published on 21 November 2016