De-turfing Hadrian’s Wall

I have argued the postholes found on the berm of Hadrian’s Wall are the remains of the a timber rampart, which together with the Turf Wall, formed the primary rampart and ditch phase of the frontier.[here] Recent work by Eric Graafstal also suggests the turf wall was the very first part of Hadrian’s Wall, and would date this phase to 119 AD, although the author believes that the Turf Wall was built in isolation against the tribes in SW Scotland [1].  Unfortunately, this leaves the Turf Wall dangling, awaiting the eventual arrival of the Stone Wall in centre of the country, and also presupposes the Northerners lacked the tactical ability to outflank the Romans by simply riding round it, rendering it useless.  But that’s not the only problem with a Wall made of turf; is such a thing likely, practical, and is there any real evidence to support it?

26. Impossible Drains

All journeys start somewhere, even those in the mind, and the mental expedition exploring the uncharted depths of my ignorance that became Theoretical Structural Archaeology started at a site called Orsett ‘Cock’, to the north of the Thames in Essex.

The Orsett ‘Cock’ enclosure, Essex, during the 1976 excavation,
showing the position of buildings S1 and S9, discussed below.

The Orsett ‘Cock’ enclosure had, appropriately for an archaeological site, taken its name from a local hostelry, the ‘Cock’ Inn. The complete liability this would become in a Google search could not have been foreseen when the site was excavated in 1976 (hereafter to be known as the Orsett Enclosure, so as not to attract unwarranted attention). After a brief interim report,[1] the site vanished into the great black hole of unpublished sites known as ‘The Backlog’.

25. A world of Invisible Walls

How to account for things that are invisible is always tricky, as priests would no doubt testify, and in some respects archaeologists have a comparable problem to religions, in that what we are asking you to comprehend and visualise happened a long time ago. However, archaeologists, unlike priests, are happy to admit (if pushed) that what we are asking you believe is an educated guess, even if, as often the case, we have a story and we’re sticking to it with almost religious zeal.

For British prehistory the problem is that some significant pieces of the visual jigsaw have been destroyed forever, and they have become ‘archaeologically invisible’. I can tell what the woods and the trees looked like -- I have photos that must be fairly close – but the evidence for the human part, particularly the built environment where human life is played out, is somewhat sketchy.

19. The proper study of mankind is postholes

With all due apologies to Alexander Pope [1], and John Collis [2], postholes are quite important, but it is what they represent, the prehistoric built environment, that gives them their significance to archaeology.

An excavated posthole

The central importance of the built environment to archaeology, to its original inhabitants, and to builders was explored in a series of earlier articles, as was the basic problem of archaeological sites with lots of postholes that, once any roundhouses have been extracted, remain uninterpreted.

17. Not Seeing the Wood or the Trees

Prehistoric material culture was mostly made of wood, yet most archaeologists largely have studied the inorganic aspects of culture, since timber so rarely survives. However, it is still important to consider where the wood that we didn't find came from.

15. Living in lakes and other perennial problems

Throughout Prehistoric Europe settlements were built on artificial islands in lakes. These varied in size from small towns to individual houses. These islands were usually constructed from timber piles and built up with local materials such as tree trunks, brushwood, clay, and stones. These artificial island settlements are known as ‘crannógs’ in Ireland and Scotland, where they are common in the Iron Age.

A modern reconstruction of an Iron Age crannóg on Loch Tay, Scotland [1].

12. Treasure, ruins and myths

Treasure, ruins, and myths are about as good as it gets in archaeology, and mystery is omnipresent, but of course none of these things interest professional archaeologists, not one bit, not at all. Archaeologists value things that are more rare and precious than treasure.
To find somebody’s best belongings stacked in a tomb is not that uncommon, but to find them in the space where they belong and interacted with their owner is extraordinary. The chance survival of built environments, complete with contents, is probably the most valuable type of archaeological find imaginable, and luckily, it has happened a number of times.

Roman interior design: a fresco from Pompeii

11. A Strange Receding Past

The past is much further away than it used to be. The rapid change in our culture over a few generations has disconnected people from the countryside and agriculture, as well as from the skills, crafts, and materials of previous generations. The past will always be mysterious, because the vast majority of it leaves no trace and is ‘invisible’ to archaeology. These invisible bits, like buildings, we have to make up or imagine.


Increasingly, the past has become the realm of theory, abstract thought, and introspection for archaeologists operating in the wide-open spaces of our ignorance. Novel theoretical approaches are borrowed from other subjects with obscure and unfamiliar vocabularies, and these are used to conceptualise our lack of understanding. If all else fails in the strange world we are reconstructing, archaeologists pass off what we don't understand as ‘ritual’. It therefore passeth all understanding and can be used to justify all manner of absurdity.




How the original palimpsest at Mucking in Essex was ‘solved’. A: All features. B: Roundhouses & (4-post?) structures located. C: Simplified Plan. D: Reconstruction [1]

7. Seeing is believing.

In 1817, Samuel Taylor Coleridge, an English poet and philosopher, came up with a theory about the readiness of people to accept ideas that are clearly fantastic and unreal when engaging with the arts, and the phrase "willing suspension of disbelief" entered the language. Television and literature are obvious examples, where we are prepared to suspend our critical faculties and our everyday model of reality in return for entertainment: We know it's not real, but we are prepared to forget that, in return for the emotional experience the medium induces.


This is particularly true of the visual media, which do not come close to our real visual experience of life; yet we are happy to accept images far removed from our reality. Images are powerful – “worth a thousand words” -- as the proverb goes, because they can convey large amounts of information very quickly, are easily memorised and recalled, and are capable of eliciting an emotional response. Images are far more powerful than text. Much of what people know about the world beyond their immediate experience, they absorb through visual media.

6. Little Woodbury’s bastard children

Roundhouses were real buildings, and the plans of their foundations are characterised by the geometry and accuracy that any large timber frame structure requires. The obligatory search for circles in posthole palimpsests has inevitably thrown up other slightly oval and irregular patterns that are still interpreted as ‘roundhouses’.
I will illustrate this difficult point with examples produced by former colleagues in Essex. At least they were aware of my views, and so have had some chance to defend themselves. For the record, I will offer an alternative view of what they found in a later blog.

5. Roundhouses and other circular arguments

One the most fundamental and frustrating truths about archaeological excavation, tacitly accepted by practitioners, is that on most sites, a significant number of features will never be properly understood or explained.


The 1939 Little Woodbury excavation has proved to be a watershed for many aspects of archaeology of Southern England, not least because Bersu could explain and interpret the majority of the features he found, and in so doing provided the first model of the built environment of prehistoric Britain.

4. Once upon a time, in a place called Little Woodbury ...

There are no real starting points in history; every event is dependent on an infinite number of prior events having happened since time began. But it's fun to play the game.
One of the more obscure consequences of the rise of Hitler and the Nazis in Germany was the arrival in England in 1936 of Gerhard and Maria Bersu. Gerhard Bersu was an experienced German archaeologist who had been forced from office on account of his Jewish background.  left; Gerhard Bersu
In 1938 he was invited by the Prehistoric Society to excavate a site at Little Woodbury.[1] The site was one of an increasing collection of ‘cropmark’ sites discovered through aerial photography since the First World War.

3. How do archaeologists recognize buildings and structures?

Let us be perfectly clear from the outset: the foundations of prehistoric buildings were not continuous, being formed by intermittent posts. In more modern buildings, the foundations are usually continuous strips set in the ground, marking the position of ‘load-bearing walls’. Since all the elements of the modern foundation are joined together, it is easy to understand the plan of the building. However, working out which posthole goes with which prehistoric structure, often without evidence of walls and floors, is not easy. In fact it is very difficult, and in many instances, probably impossible.



Part of the site at Mucking, Essex [1], a collection of postholes so complex that it prompted the excavators [2] to compare it as a palimpsest – an ancient document that has been overwritten several times.

2. How archaeologists find the evidence for the Prehistoric built Environment.

It is important, before considering the evidence for the prehistoric built environment, to consider how, and in what circumstances, it was gathered.


An archaeological excavation is not a double blind clinical trial of a new drug; it's not that vital to society, and is resourced accordingly. Also, it’s just not that objective. Archaeological excavators are not scientists, and excavations are not experiments: they cannot be repeated because, ironically, excavation actually destroys much of the evidence it is studying.

1. What is the evidence for the built environment in prehistory?

The surviving evidence for the ancient built environment mainly consists of postholes. These are the archaeological remains of small pits dug into the ground to accommodate timber posts, typically 0.20 –0.40m in diameter and of similar depth. Postholes are a type of feature, a term archaeologists use to describe the individual impressions left in the ground by people digging holes in the past. Other common types of features are pits, ditches, and gullies.







An archaeological site plan from Orsett in Essex, showing a complex pattern of postholes, ditches, and gullies [1].

What is this Blog about?

I am a professional archaeologist who has spent 20 years trying to gain an understanding of timber building and architecture in the Prehistoric Britain, and this blog is the only way I have to disseminate the things I have found out and the methodology I use.

Its a vast subject, so in this blog I intend to try and concentrate on timber buildings and structures from a selection of sites in the southern half of England from the period 2000BC -500AD.

I am writing this blog so that anyone can read it. It takes longer, but has the advantage of ensuring that archaeologists will be able to follow it too. Its not just that archaeologists are very diverse in their intellectual backgrounds and approaches, but also because they bring with them far more preconceptions. It is difficult to remember what I understood about the subject before I began this study.

The blog is not heavily referenced, and it contains a few jokes. I will try to draw in material from a wide range of unrelated areas of archaeology to broaden its appeal and provide a wider range of visual images. It is to be hoped that readers may find other interesting aspects of archaeology and the ancient world to follow up from this blog.