Why were hillforts built? What was their purpose? It is a question which has caused a considerable amount of debate and argument over the last two hundred years. The answer is that no one really knows for certain. There are plenty of suggestions, some more plausible than others, but as is often the way, the more we learn of these impressive structures, the more questions are raised.
It is often thought that hillforts were built largely in what is known as the Iron Age, and that the building of them came to an end with the arrival of the Romans in 43AD. This would be largely correct. However, it is becoming increasing clear that some were initially built at the end of the Bronze Age, for reasons that are no clearer than for those built entirely in the Iron Age. While it is rare that new hillforts were built after the end of the Roman occupation in the 5th century, a considerable amount of hillforts, especially in the south of England were re-occupied and re-modelled in the centuries that followed, with evidence of a change in status and usage. In truth, what we have is the incredible fact that hillforts were in active use for near enough one thousand years, a length of time that would take us back to before the Norman Conquest. It seems entirely logical then, to accept that hillforts in that time have had a variety of different uses to a variety of different peoples, in a variety of different places in the British Isles.
What is clear from the construction of these hillforts is the sheer scale of the work required. Even the smallest known hillfort in North East Wales, Moel y Gaer at Llantysilio would have required enormous quantities of manpower and resources, using, by today’s standards the most basic of tools, clearing vast areas of woodland. Penycloddiau in the Clwydians is thought to be the largest hillfort in Wales, and the effort to build this huge fort is breath taking. It suggests a level of organisation and co-operation, an unswerving belief in the importance of the project that is frankly staggering, for a purpose or purposes that in their vagueness are the more frustrating in the face of such enormous effort and focus. There has been speculation that their building was done by coercion, by slaves in effect, but little in the archaeological record backs that theory. The more likely explanation is that they were an act of a community single-minded in its objective to produce a monument to themselves and their community, as well as to impress visitors.
However, for many, many years, the most obvious suggestion for the purpose of hillforts was, as the name suggests, fortified enclosures, protection from attack, or centres of military rule. There are problems with this suggestion of course, but it seems likely from what we know that they did have to some extent a military purpose. There is evidence from southern England, for instance that hillforts were subjected to attack, with evidence of burning and containing the remains of bodies that died in violence. However, it is likely that this military function was not the only purpose, perhaps even the primary purpose for their building. Consider the much later castles built by the Normans. Despite their impressive military demeanour, they were never simply military forts, but centres of administration, business and colonial settlement. We seem to struggle with the possibility that hillforts had the same function within the societies that they existed within. There is little evidence, as far as I can tell, of the hillforts of North East Wales being subjected to attack, the speculation of the rather excitable, Willoughby Gardner and his perceived assault on Moel y Gaer Llanbedr aside. Indeed, the evidence would suggest that the purpose of hillforts changed through their lifetimes, and those of the communities about them.
Still, the archaeological evidence has proven time and time again that these enclosures were fortified, and in this the hillforts of North East Wales are no different. Whether univallate (single rampart) or multivallate (multi-rampart), they were fortified, usually with an earthen or sometimes a stone embankment topped with a wooden palisade. The ditch beneath these walls would be deep and often rock cut, the gates with accompanying guard chambers. In short, they were imposing, intimidating structures, and this no doubt was an intention. Even today, driving south on the A5 past the old hillfort at Oswestry is to be a little taken aback by the scale of the thing, and to walk within the remains of Caer Drewyn’s stone walls leaves one in no doubt as to its power.
In considering a primarily military purpose, however, consider the enormity of Penycloddiau. It would have been almost impossible to defend an enclosure of that size, whether a direct attack or a siege. It would have required hundreds to defend the hillfort, thousands to successfully attack it, numbers that are unlikely to have existed during the time of its active existence. Given that the evidence of warfare (of which there is much better from the Neolithic and Bronze Age eras) suggests it would most likely have been inter-tribal, rather than tribal, those numbers would just not have been possible.
Add to this the issue of water. Many hillforts did not have a reliable water source within the enclosure itself, with springs and wells situated outside the ramparts. This would suggest that any type of siege would have either been non-existent or a very short business indeed. No military leader of any merit would allow a fortified structure to be devoid of a source of fresh water. No leader would last long if he suggested building a wholly military structure without one. It would suggest that siege was not a seriously considered military concept to these peoples.
And if these structures were primarily military, is it not reasonable to suggest that weapons, iron weapons would be a fairly common archaeological find? Well, unfortunately, archaeologists are more likely to find Bronze Age era weapons than any clearly identifiable as Iron Age or contemporary with the building of the fort. What does that suggest? It could possibly indicate that these structures were so successful that they were rarely attacked. It could indicate that they were attacked with less effective, but generally more impressive looking bronze weapons. When evidence of battle is apparent, it is unmistakeable, so it follows that a lack of battle is also telling, and there is a distinct lack of evidence suggesting that the hillforts of North East Wales were subjected to any real warfare. In fact, given that there are something near to 3300 hillforts in Britain, the lack of evident warfare would dramatically underline that their purpose was more complicated than as purely military.
There is also the question of location. There are four hillforts within the Clwydian Range (five, if you wish to include the hillfort at Bodfari). Penycloddiau and Moel Arthur are close to each other, as are Moel y Gaer (Llanbedr) and Moel Fenlli. As primarily military structures, that just seems too close, too clustered to be effective, unless they were defended against each other, of course. And what is to be made of the fact that none of these hillforts was built on the highest peak, Moel Famau at 554 metres? Having a military structure overlooked by higher ground is almost unheard of, for obvious reasons. It would suggest that despite appearances, the hillforts were something other than just military structures.
However, there can be no doubt that hillforts served some kind of military function. One look upon the ramparts or from them, an attempt to climb the slope to the enclosure, negotiate the sometimes very intricate network of approach routes, and you will appreciate that defence was in the mind of the designers. Yet, how effective were they? It is hard to say, for several reasons. As has already been stated, evidence for conflict is sparse, virtually non-existent in North East Wales. It is likely that warfare in the late Bronze Age, Iron Age was a small scale, if intense affair. And consider the Roman invasion after 43 AD. Surely holding off the Roman Army was the litmus test of an effective defence. But, as far as is known, no hillfort in Britain, and possibly the European continent ever successfully withstood a Roman attack or siege. Would it not be likely that hillforts would have been remodelled in light of this new, highly organised and successful enemy appearing in the lands of the Iron Age peoples? As far as the archaeological record can tell us, the Roman Army had little to do with the hillforts of North East Wales. They built a road through the Vale of Clwyd, directly beneath the Clwydian Range and its impressive hillforts – hardly the act of an invading army that felt at risk. It is likely then, that a military function was only part of the reason for their construction, and that part focused on others within their tribe, as opposed to the later Roman encroachment. The fact that some British hillforts in the south of England were besieged by the Romans in the first and second centuries was simply because there was nowhere better for the native peoples to defend themselves. More likely, they were designed to beat back smaller scale raids, even to deter such attacks in the first place. Hence, an intimidating façade rather than a means of holding off a grand attack.
A good theory is that they were built as enclosures to collect, defend and control agricultural produce, perhaps on a seasonal basis. The lack of buildings within the enclosures is telling, with wide open spaces that were more conducive to penning large numbers of animals, perhaps at times of agricultural fairs, the start of droving and even trading events. And, it is thought that the end of the Bronze Age was heralded by not just the advent of iron into the culture of the British Isles, but possibly by changes in climate and increases in population. Food became more scare and required peoples to work closely to ensure the survival of a community. It would explain why hillforts would not, and did not successfully withstand siege, because simply put they were never really designed to do so. There is good evidence of storage areas within these enclosures; open spaces and pits where produce and livestock could have been kept. There is evidence of impressive technological developments ensuring the preservation of produce. It is probable then that hillforts were built for a community to store its food, to protect that food and themselves from opportunistic raids from struggling peoples, possibly even as trading centres.
At the mention of trade, it is worth noting that trading networks would have likely as not collapsed at the end of the Bronze Age, and that movement of groups, large or small was more suspicious now and needed monitoring? But trade of some kind would have continued, and would have needed policing. A look at the position of Caer Drewyn is telling. At the western tip of the Llantysilio Mountains, it is impressively placed to control the flow of traffic through the Vale of Llangollen beneath the Berwyns and north through the Vale of Clwyd. Is it important that Caer Drewyn, of all the hillforts in the area seems to be the most militarily practical, with its astonishing stone walls? In short, was Caer Drewyn built to control the lucrative routes of goods from Ireland into the heartland of Britain, as well from the coastal areas of North East Wales?
There are some that believe that hillforts were ceremonial centres. Temples, Romano-British and earlier have been found within the enclosures. At Penycloddiau, there is a Bronze Age barrow within the fort. Not far from Ruthin there is evidence of a considerable Romano-British temple site, possibly of huge cultural importance. At certain other hillforts, the Romans themselves built temples within the enclosures, including notably at South Cadbury. Is it possible that hillforts relate to these sites.
As for life within the hillforts, it would have been one of mud, smoke and noise. While there is evidence of habitation within hillforts in general, the number of roundhouses so far discovered would suggest that the populations of these structures were sparse. In North East Wales, Moel Fenlli is by far the most obviously inhabited, with near enough 60 identified roundhouse platforms. But, on the other hand, the huge site of Penycloddiau bears witness to only around 30. A far cry from Yeavering Bell in Northumbria, with some 125 roundhouse platforms thus discovered in an enclosed area half the size of Penycloddiau. Larger roundhouses, of which there is some limited evidence, might well have been for the ruling elite, while smaller huts would have been the workshops and homes for a mercantile or crafting class. There is some evidence of route ways threading through the buildings, and in sites such as Maiden Castle in Dorset, those pathways suggest something more akin to a small town. Some of these buildings were apparently built on stilts, probably to protect them from animals or the effects of the weather. As suggested, open areas would have been used for penning livestock, and there would then of course have been the resultant smell. Wood and smithy smoke, the noise of labour and argument and the ever-present mud would have been the truth of life within the enclosure.
Essentially then, it is fruitless and a little naïve to suggest that hillforts were built purely for one function. It is probable that they served all manner of roles within the communities that used them, whether those societies were at the end of the Bronze Age, Iron Age, Post-Roman or even early medieval. In a lifespan of nearly one thousand years, hillforts would have provided something different to a new generation. Cadbury Castle in Somerset was defended by the Durotriges against the Romans in around 70AD, remodelled by the Romano-British against the Anglo-Saxon incursions of the 6th century and used as an emergency mint by the Anglo-Saxons of the 11th century in the face of Viking attacks. The role of hillforts would have changed over the centuries they were used, earlier uses incorporated into later ones. Today they stand as huge monuments to the endeavour and the needs of societies that seem that little closer to us for the remains of these huge hillforts.