Tag Archives: Conservation Management Plan

Saved by the railways, Offa’s Dyke will survive forever!

Heritage conservation is concerned for the long-term future of our ancient monuments, but this is usually considered in terms of the immediate coming centuries. However, what the survival of monuments over millennia? How can we, and should we, consider the future-proofing of our valued ancient monuments for thousands of years to come?

I’d like to suggest that Britain’s longest ancient monument – Offa’s Dyke – will likely survive longest – for thousands, if not tens of thousands, of years – not where it is situated in woodland or farmland, or where it is protected as a scheduled ancient monument, but where it has already been sealed by 19th-century railway embankments.


The conservation of Britain’s largest ancient monument – Offa’s Dyke – is a pressing topic for archaeological and heritage debate. Regarded as built as an early medieval (Mercian) frontier work of the late 8th century to control movement and protect territory against Welsh rivals, it is a stupendous military, economic and ideological edifice. Yet despite its enormous scale and length (both of which remain issues that are hotly debated), this monument’s long-term future is uncertain.

Offa’s Dyke runs for large sections of over 170 miles intermittently from Gloucestershire to Flintshire. In some places it may have never been present, marked instead by rivers and other features. In further places it may have been constructed by was already denuded by medieval agricultural activities. Yet so much of the damage to the monument has been the result of 19th-early 21st-century agricultural activities, extractive industries, road and rail building, development for housing and other construction activities. On a far more modest level, it has been affected by erosion caused by walkers enjoying it as a public right of way and long-distant route: the Offa’s Dyke Path. Beyond all of these factors, Offa’s Dyke is affected by passive neglect as it is damaged by vegetation, burrowing animals and animal husbandry and farming practices, as well as by wind and water action by the elements (especially where it runs along steep slopes and in river valleys).

Conserving Offa’s Dyke for future generations is therefore not as strightforward as it might seem. Looking forward through the 21st century, the monument faces many potential risks to its long-term future including not only the processes outlined above, but also our disinterest and inability to conceptualise its monumental scale and historical significance. This is why the Offa’s Dyke Association, Historic England and Cadw are working together and funding an eagerly awaited Conservation Management Plan of the monument.

But let’s take a really long-term view for a moment. Which parts of Offa’s Dyke will survive longest?

Offa’s Dyke has been a dominant feature of the British landscape since at least the late 8th century: it survives in patches of staggering monumental scale, with a ditch up to 2-3m deep and bank up to 4m high, and a horizontal breadth of up to 20m. It has endured in varying scales for over 1220-1260 years! Surely, even if subject to ongoing damage, it will remain a feature through the 21st and 22nd centuries, and arguably the 31st and 32rd centuries AD, perhaps even until the 41st and 42nd centuries AD, perhaps long after humans have vanished from the planet. For the long term, and while humans are still here, surely scheduling the ancient monument will best ensure its survival for millennia to come?

Certainly I support the legal protection afforded to Offa’s Dye, but I’d also like to suggest that for all our conservation strategies, the sections of Offa’s Dyke likely to survive longest aren’t those subject to scheduling. Instead, I propose those that have already been ‘destroyed’ will survive longest. Buried sections of the ditch at many  locations along its length are well-preserved out of site, but in terms of the bank’s survival, I’d propose railways have already ‘saved’ some sections of Offa’s Dyke for future millennia by late 19th-century railway embankments.

Railways and the Dyke

Offa’s Dyke is crossed by railway lines in multiple locations in its northern stretches associated with the Denbighshire coalfield. Many of these railway lines are parts of wider industrial operations that have destroyed the Dyke. For instance, at Ruabon the GWR crosses the Dyke in a cutting, as well as being damaged by road and rail at Ruabon Brick and Terra Cotta Works, cut by the Wrexham and Minera line at Cae-llo Brick Works, destroyed by sidings at Vron Colliery, and damaged by being cut by the Wrexham and Minera joint line at both Ffrith Hall and also at Pontystain Crossing.

Yet there are at least two locations where it seems that Offa’s Dyke has been buried and not necessarily destroyed by railway construction. In these locations, Offa’s Dyke’s bank and ditch might be reasonably expected to survive as well-preserved buried features since they were sealed beneath metres and metres of overburden during the construction of railway embankments. I make this argument presuming that railway embankments were built by a human workforce: not by large-scale earth-moving devices that might have damaged and destroyed the bank during the embankment’s creation (therefore contrasting with modern road-building). I’m happy to be corrected on this point.

First of these is at Brymbo Colliery where sidings are laid out over Offa’s Dyke with coal waste and now landscaped.

Brymbo Colliery
Offa’s Dyke runs into the sidings at the Wonder Pit, Brymbo

The second is a site I visited for the first time yesterday: north of Pentrebychan Crematorium in Wrexham borough. Here, the line of Offa’s Dyke was crossed by the Wrexham-Rhosllanerchrugog railway line. Constructed in the 1880s and 90s, it was opened to passenger traffic from 1902.

Offa’s Dyke crossed by the line of the Wrexham-Rhos railway line

My only reservation is that, from the Ordnance Survey map, it might be taken to suggest that the line of the Dyke is denuded by the building of the bridge over a lane joining farm fields. However, on close inspection, it seems that the bank should be largely preserved, at least at the northern end, beneath the railway embankment just east of the crossing.

Looking S from the edge of Offa’s Dyke – one can see the line of the Dyke approaching the embankment at an angle such that it will be preserved beneath the embankment on the east (left) of view.
A denuded bank of Offa’s Dyke runs N towards the Wrexham-Rhosllanerchrugog-Acrefair railway embankment

So will Offa’s Dyke be saved by the railways? Thinking of the deep-time persistence of this important monument might require we think of places where the Dyke has already disappeared, not where it is scheduled and preserved.


Offa’s Dyke: Conservation Conversations

Paul Belford writes on his blog:

The conservation of Offa’s Dyke has been the focus of two events in recent weeks. Both were hosted by the Offa’s Dyke Association (ODA) and took place at the delightful Offa’s Dyke Centre in Knighton. The first event, on 23 March, was the third meeting of the Offa’s Dyke Collaboratory; the second, on 12 April, was a formal consultation on a new Conservation Management Plan (CMP).


The Offa’s Dyke Centre in Knighton, home of the Offa’s Dyke Association.

Rather than providing a ‘blow-by-blow’ account of the events, this post summarises some of the main issues around the CMP which were articulated at both meetings.

First, some background. The Offa’s Dyke Collaboratory was established after discussions in 2015 and 2016 around Keith Ray’s monumental book on the Dyke. A number of us felt that some sort of loose collaboration was needed between people and organisations who had been most actively engaged in research, and were likely to be so in the future. The Collaboratory is a mechanism for engagement between academics, communities and professionals; so far three events have been held and fourth is being planned for later in 2018. The papers presented at the Collaboratory event in March can be found on the Offa’s Dyke Collaboratory website – along with more information about the Collaboratory, and its events and activities.

Meanwhile, in 2017 and 2018, Historic England and Cadw jointly funded the production of a Conservation Management Plan for the Dyke. This work – which was overseen by the ODA and undertaken by Andre Berry – was the first re-appraisal of the conservation issues surrounding the Dyke since the original Conservation Statement was produced in 2000. The new plan has not yet been published, but is in the final stages of production. From what we have seen so far it looks a very thorough piece of work providing a comprehensive and detailed survey of the condition of the Dyke, and an analysis of the key threats to it. The meeting in April was split into two parts – archaeology in the morning, and access (including the relationship between the Dyke and the Offa’s Dyke Path) in the afternoon.


Offa’s Dyke at Llanfair Hill, Shropshire.

Discussion topics ranged from the minutiae of data management to the possibility of Offa-branded food and tourism products. Three areas stood out for me.

What about the data? The CMP has produced an enormous quantity of data. Of course there is already a great deal of information on the Dyke already held by the Historic Environment Records (HERs) of the three English counties through which the Dyke passes (GloucestershireHerefordshire and Shropshire), and by the Clwyd-Powys Archaeological Trust (CPAT) in Wales. There was some discussion about how the data gathered by the CMP process is integrated into the HERs. The creation of a separate database would create all sorts of issues around adding new data to it, or accessing the data already in it. It is also not yet completely clear who owns the data and who may use it. It was agreed that more thought could perhaps have been given to this at the outset of the CMP project. Fortunately the four HER Officers are working closely to resolve some of the (minor) technical issues, and there was clear agreement that this will be a priority for the CMP. Indeed further cross-border co-operation in this area would be a positive outcome more generally for the longer term.

Informed conservation? The management of the trail needs careful co-ordination with historic environment needs: the CMP has clearly highlighted the need for better co-ordination between the creation of path infrastructure and monument conservation. However it was clear that resources to manage the National Trail were already stretched and likely to be more so in the future. The CMP has also prepared draft archaeological guidance. This is welcome in principle, but the emphasis of the draft proposals sat uncomfortably with many people. Some questioned whether the proposed priorities represented the best use of resources. Many of those present felt that potential opportunities to learn more about the Dyke were not being fully considered. In many places the monument is poorly understood, or even not known at all, and excavation would enable conservation to be fully informed by better understanding. A more ambitious, imaginative and creative approach would be welcome.

Whose Dyke is it anyway? The increasing divergence between England and Wales in historic environment legislation and resourcing (for which see my recent paper on politics and heritage in Wales), together with the different approaches in the various local authority areas, means that ‘ownership’ – of research and conservation, and the data that can be derived from projects – is potentially fragmented. Moreover, archaeologists and ‘heritage bureaucrats’ aren’t the only stakeholders. There is a long tradition of non-professional engagement with the Dyke. Sometimes this has been under the umbrella of community-focussed heritage projects by professional bodies such as CPAT and Herefordshire Archaeology. Elsewhere individual groups have developed more independent approaches, such as the recent development of the CoSSM project. The ODA itself has been instrumental in developing a much wider understanding of the Dyke’s historical role, and has also generated a great deal of enthusiasm for the landscape through which it passes. Much of this enthusiasm is driven by aspects that are not directly related to cultural heritage.

CPAT excavations of the Whitford Dyke (Flintshire) in 2012. Photo copyright CPAT (3551-0033). 

The CMP is an excellent piece of work, and a sound basis from which to start. Everyone agreed that there must be more archaeological research, better integration of data, improvements to access, and greater community and landowner awareness. However substantial funding for any large-scale project – whether for conservation, access or research – seems unlikely to materialise in the current climate. Replicating the CMP walkover survey at regular intervals would seem to be the most cost-effective way of monitoring the condition of the monument. Conservation needs to be informed by understanding, and – as many said at the meeting – our understanding is somewhat limited (I articulated three areas of particular concern in a previous post).

The best approach will be to embed the CMP findings into the HERs so that they can inform more localised research frameworks and investigation projects. These in turn can be delivered under the umbrella of the Offa’s Dyke Collaboratory, to ensure synergy between research, conservation and public benefit.

It will be interesting to see to what extent the discussions at both meetings – but particularly the formal consultation – will have on the final form of the CMP.

These are some initial thoughts, and they may cohere more gracefully in time for my presentation on the conservation of Offa’s Dyke at the forthcoming CIfA Conference in a couple of weeks.