13 Things You Didn’t Know About Hillforts — The Real Story Behind Britain’s Ancient Earthworks

June 7, 2025 Trebor2510

Contents

1 Introduction
2 Conclusion
- - 2.0.1 What Archaeology Must Prove To Call Hillforts “Forts”.
3 Exploring Prehistoric Britain: A Journey Through Time
4 Further Reading
5 Other Blogs

Introduction

Hillforts have long been cast as the mighty defensive bastions of prehistoric Britain, iconic symbols of Iron Age tribal warfare and territorial defence. But if you peel back the layers of archaeological evidence, a very different, far more complex picture emerges. While some hillforts were adapted for military use during later periods—particularly during Roman expansion—the majority were multifunctional hubs serving economic, ceremonial, territorial, and social roles rather than purely defensive purposes.

Below, we unravel 13 surprising facts that challenge the traditional fortress narrative, shedding light on the true nature of hillforts across Britain and Ireland. Prepare to rethink what you thought you knew.

13 Things You Didn’t Know About Hillforts — Hillforts have long been cast as the mighty defensive bastions of prehistoric Britain, iconic symbols of Iron Age tribal warfare and territorial defence

1. Hillfort Classifications Are Outdated and Over-Simplified

For nearly a century, archaeologists have tried to neatly categorize hillforts based on size, location, rampart construction, and age. Early scholars like Sir Mortimer Wheeler and later Barry Cunliffe developed classification schemes grouping hillforts into types such as early hilltop enclosures over 10 hectares, smaller settlements of 1–3 hectares, early univallate forts, and more complex multivallate sites. These categories aimed to make sense of the diversity by assigning function and status, often equating larger or more complex sites with defensive importance.

However, these classifications are increasingly questioned because they lean heavily on limited physical evidence and overlook the social and economic functions of these sites. For example, a large enclosure doesn’t necessarily mean a military fortress; it could be a ceremonial gathering place or a centre for trade. Likewise, a simple earthwork might have deep ritual significance rather than being a mere settlement defence. This simplified framework risks distorting the true roles these structures played in prehistoric societies.

By focusing too much on size and fortification features, scholars have missed the multifunctional nature of hillforts. Archaeological evidence now points to a more nuanced understanding: these sites often combined social, economic, political, and ritual functions alongside occasional defensive adaptations. We must therefore treat traditional categories with caution and embrace complexity.

2. The “Fortress” Definition Has Stuck For Too Long

The classical definition of a hillfort, as “a fortified refuge or defended habitation on elevated ground,” still dominates textbooks and popular understanding. Wikipedia and many reference works place hillforts squarely in the Bronze or Iron Age and depict them as military installations designed to control territory and repel attackers. Their defining features are steep earthworks, ramparts, palisades, and ditches, strategically placed to take advantage of high ground.

While this definition neatly fits some later hillforts, it oversimplifies a wide array of prehistoric enclosures that often lack convincing military architecture or evidence of warfare. Moreover, it ignores that many of these sites have much older origins, with some showing continuity of use stretching back thousands of years before the Iron Age, into the Neolithic or even Mesolithic periods. The persistence of this fortress-centric view obscures the diverse social realities of prehistoric communities.

Holding on to this entrenched definition restricts archaeological interpretation and public perception. It encourages viewing hillforts as relics of constant warfare rather than appreciating their complex social, ceremonial, and economic dimensions. The reality, as recent research shows, is far richer and more varied.

3. Hillforts Were Around Before the Iron Age

Many people associate hillforts exclusively with the Iron Age, roughly 800 BC to AD 43 in Britain. However, extensive excavations reveal that numerous hillforts have earlier origins, dating back to the Late Bronze Age and even Neolithic times. Cultures such as the Urnfield (1300–750 BC), Hallstatt (1200–500 BC), and La Tène (600 BC–50 AD) saw the proliferation of hillforts, but the groundwork was laid much earlier.

For instance, archaeological layers in famous sites like Maiden Castle and Danebury contain flint tools and pottery shards from the Neolithic and Mesolithic eras. This pushes back their initial construction or use by several millennia before the traditionally accepted Iron Age period.

This deep time depth challenges the fortress narrative by suggesting many hillforts began as community or ritual centres long before any significant tribal warfare. Their repeated reuse over thousands of years indicates multifunctional importance beyond defence and highlights the continuity and adaptation of prehistoric societies.

4. Population Growth Doesn’t Match the Fortress Theory

Prehistoric Britain’s population dynamics don’t quite fit with the idea of a landscape littered with defensive forts. Estimates suggest that during the Neolithic (circa 5000 BC), Europe’s population hovered between 2 and 5 million. By the Late Iron Age, it had swelled to roughly 15 to 30 million. But except for dense pockets like Greece and Italy, most settlements in Britain were small, often supporting fewer than 50 people.

Hillforts stand out as exceptions, accommodating communities as large as 1,000, but such numbers were rare. The later appearance of oppida—urban centers housing up to 10,000—reflects increasing societal complexity. However, the distribution and density of hillforts do not correlate with an equally dense, heavily militarized population needing constant defense.

The logistical challenge of defending thousands of these hillforts, each requiring a substantial population of warriors and support staff, becomes apparent when population estimates are compared to fort numbers. There simply weren’t enough people to maintain standing armies or garrisons in every hillfort, undermining the fortress theory.

5. Hillforts Were NOT Evenly Distributed — Which Defies Pure Defence Logic

If hillforts were purely defensive, you’d expect them to be evenly spaced, strategically located to guard borders or resources. But the reality is messier. Over 3,300 hillforts are clustered unevenly across the British Isles. Take the Isle of Man—a tiny island of 572 square kilometres—with an astounding 32 hillforts. That’s roughly one hillfort every 5 to 6 square kilometres, far too dense to be defensible or necessary purely for military protection.

Additionally, about 30% of hillforts hug coastlines, with another 50% near prehistoric river systems. This heavy concentration around water suggests that control of waterways, trade, and communication routes were important considerations. Another 70% are near quarrying or resource extraction zones, linking hillforts to economic activity rather than just defense.

Such distribution patterns are inconsistent with a landscape dominated by warring tribes guarding fixed territories. Instead, they imply hillforts functioned as hubs for trade, social interaction, resource management, and ritual gatherings tied closely to natural and economic landscapes.

6. Little Evidence of Warfare or Prolonged Occupation

If hillforts were military bastions, we would expect abundant archaeological evidence of sustained occupation, such as permanent housing, weapon caches, and clear defensive structures like palisades or gatehouses. We would also expect to find mass graves or layers of debris from sieges.

Yet, surprisingly, few hillforts show such evidence. Many have signs of only episodic or seasonal occupation. Archaeologists rarely find weapons stockpiles or large-scale battle remains inside hillforts. Defensive architectural features are often minimal or absent, and many ditches have shapes inconsistent with fortification—flat-bottomed, not steep and V-shaped.

This absence of clear martial evidence points to alternative interpretations: hillforts served multiple roles, perhaps acting as gathering places for trade, ritual ceremonies, or political meetings, with defense being a secondary or occasional function.

7. Danebury Hillfort Is Probably Older and Less “Fortress” Than Thought

Danebury in Hampshire is often cited as a classic Iron Age hillfort, extensively excavated by Barry Cunliffe in the 1970s. While traditionally dated to the 6th century BC and used for about 500 years, recent carbon dating and flint finds suggest it began as a Late Bronze Age stock enclosure 3,000 years ago. Some evidence even points to Neolithic or Mesolithic origins.

Excavations uncovered thousands of flints spanning multiple prehistoric periods, alongside Beaker pottery, challenging the notion that Danebury was a purely Iron Age military installation. Furthermore, LiDAR technology revealed a linear earthwork or dyke connected to the fort’s outer ditch—possibly a prehistoric waterway—hinting that Danebury might have been linked by boat transport rather than isolated on a hilltop.

Its ditches have soil deposited mostly on the outside rather than the inside, contradicting standard defensive designs. Together, these facts point towards Danebury functioning as a multifunctional site, involved in trade and social activities, rather than solely as a fortress.

Danebury Hill outer ditch joins to the dyke and not a new entry 1 — Danbury Showing the Ditches were connected to dykes from the paleochannel below

8. Maiden Castle’s Massive Size Was Logistically Impossible to Defend

Maiden Castle in Dorset is Britain’s largest hillfort, sprawling over 47 hectares. This sheer size would require an enormous number of defenders—estimates suggest 155 soldiers per shift, totaling around 465 to cover 24-hour protection. That’s not counting support personnel, families, and provisions.

Feeding and supplying such a large garrison would be a monumental task. Monthly food needs would include vast amounts of grain and meat, requiring extensive storage, pastureland for livestock (around 516 animals per month), and water—at least 15 deep wells, supplying almost 750,000 litres monthly. Yet, archaeological digs and LiDAR surveys reveal only a handful of residential structures and no evidence of such water management infrastructure.

Additionally, no workshops or industrial sites capable of producing weapons and armour at scale have been found. This logistical void casts serious doubt on the idea that Maiden Castle was a continuously manned military fortress rather than a large social or ritual centre.

9. Maiden Castle’s “Massacre” Is Much Less Clear-Cut Than Popular Tales

Popular accounts sometimes describe Maiden Castle as the site of a Roman siege massacre. However, excavations found only a handful of burials near entrances, with no mass graves or battlefield debris layers typical of large-scale violence.

Among the burials were an adult male with a debated projectile wound, a young woman with trauma signs, and several children—not typical combatants. Most bodies showed no direct evidence of violent death.

Over 20,000 slingstones discovered near entrances might suggest defensive stockpiles, but their purpose could also be ritualistic or related to hunting. After the supposed Roman attack, the site was largely abandoned, implying that its defensive role, if any, was limited and temporary.

10. Old Sarum Is Misunderstood as a Hillfort

Old Sarum, located in Wiltshire, is often labeled an Iron Age hillfort established around 400 BC. It later became a Roman fort and then a medieval castle site. However, its position on a floodplain island, not a prominent hill, challenges the traditional fortress narrative.

Claims of Roman roads converging there have been questioned by LiDAR and satellite data, which show no clear road leading to Bath or elsewhere. The earthworks around Old Sarum appear more consistent with water management or moated enclosures than defensive ditches. Soil spoil was found mostly outside ditches, suggesting construction to hold water rather than repel enemies.

outer ditch 2 768x410 1 — The ditch spoil is placed on the outside of the site to create a moat not inside to create a defensive bank

11. Many Hillforts May Have Been Waterborne Trade Hubs, Not Forts

Some hillfort ditches and earthworks may have functioned as prehistoric moats or canals, filled naturally due to higher ancient water tables or artificially to facilitate boat traffic. This suggests hillforts could have been accessible by water, acting as trading hubs connected through river networks.

LiDAR scans reveal links between earthworks and ancient waterways, highlighting a landscape adapted for waterborne movement rather than isolated hilltop defense. This theory fits with the frequent coastal and riverine siting of hillforts and their association with quarry and resource sites.

SU13 area captions 768x407 1 — Old Sarum is in the middle of an ancient flood plain surrounded by giant rivers

12. Economic Evidence Contradicts Military Function

True military sites like Roman forts show dense economic footprints: lost coins, markets, bathhouses, workshops, and dense habitation. Hillforts lack this. Coins are extremely rare even after coinage was common. There are no permanent markets or large public buildings supporting garrisoned troops.

Instead, hillforts yield evidence of seasonal occupation: animal enclosures, storage pits, and sparse artefacts, reflecting episodic use for trade, social gatherings, or ritual. This economic silence is a strong indicator that hillforts were not permanent military bases but multifunctional social centres

13. Hillforts Were Multifunctional Community Centres

All evidence points toward hillforts as dynamic, multifunctional hubs where prehistoric communities gathered seasonally for trade, political negotiation, rituals, and resource management. Defense may have been a later addition or an occasional function but was rarely the primary purpose.

Their diverse roles challenge the simplistic “fortress” label and invite us to rethink prehistoric Britain as a complex network of interconnected social landscapes, not a battlefield scattered with defensive works.

Conclusion

With new dating methods, LiDAR technology, and detailed excavations, the “hillfort as fortress” idea no longer holds water. We need to embrace a broader, richer understanding of these sites as centers of ancient community life, economy, and ritual.

What Archaeology Must Prove To Call Hillforts “Forts”.

To keep the “fort” label credible, archaeologists must find:.

Large permanent residences and housing clusters.

Reliable water supplies (wells, cisterns).

Dense loss of coins and trade items.

Associated civilian settlements outside gates.

Evidence of workshops making weapons and armor.

Defensible gatehouses and ramparts designed for battle.

Layers showing repeated conflict or siege trauma.

So far? – Those lines of evidence are mostly absent.

Final Thought.

Hillforts aren’t just relics of ancient warfare — they’re dynamic social landscapes, hubs of economy, ritual, and community. It’s time to move beyond outdated militaristic views and embrace their true complexity.

As the saying goes:

“Extraordinary claims require extraordinary evidence — and calling hillforts ‘forts’ without it is no longer credible archaeology.”

Exploring Prehistoric Britain: A Journey Through Time

My blog delves into the fascinating mysteries of prehistoric Britain, challenging conventional narratives and offering fresh perspectives based on cutting-edge research, particularly using LiDAR technology. I invite you to explore some key areas of my research. For example, the Wansdyke, often cited as a defensive structure, is re-examined in light of new evidence. I’ve presented my findings in my blog post Wansdyke: A British Frontier Wall – ‘Debunked’, and a Wansdyke LiDAR Flyover video further visualizes my conclusions.

My work also often challenges established archaeological dogma. I argue that many sites, such as Hambledon Hill, commonly identified as Iron Age hillforts are not what they seem. My posts Lidar Investigation Hambledon Hill – NOT an ‘Iron Age Fort’ and Unmasking the “Iron Age Hillfort” Myth explore these ideas in detail and offer an alternative view. Similarly, sites like Cissbury Ring and White Sheet Camp, also receive a re-evaluation based on LiDAR analysis in my posts Lidar Investigation Cissbury Ring through time and Lidar Investigation White Sheet Camp, revealing fascinating insights into their true purpose. I have also examined South Cadbury Castle, often linked to the mythical Camelot56.

My research also extends to the topic of ancient water management, including the role of canals and other linear earthworks. I have discussed the true origins of Car Dyke in multiple posts including Car Dyke – ABC News PodCast and Lidar Investigation Car Dyke – North Section, suggesting a Mesolithic origin2357. I also explore the misidentification of Roman aqueducts, as seen in my posts on the Great Chesters (Roman) Aqueduct. My research has also been greatly informed by my post-glacial flooding hypothesis which has helped to inform the landscape transformations over time. I have discussed this hypothesis in several posts including AI now supports my Post-Glacial Flooding Hypothesis and Exploring Britain’s Flooded Past: A Personal Journey

Finally, my blog also investigates prehistoric burial practices, as seen in Prehistoric Burial Practices of Britain and explores the mystery of Pillow Mounds, often mistaken for medieval rabbit warrens, but with a potential link to Bronze Age cremation in my posts: Pillow Mounds: A Bronze Age Legacy of Cremation? and The Mystery of Pillow Mounds: Are They Really Medieval Rabbit Warrens?. My research also includes the astronomical insights of ancient sites, for example, in Rediscovering the Winter Solstice: The Original Winter Festival. I also review new information about the construction of Stonehenge in The Stonehenge Enigma.