Blog Post

Caerfai promontory fort – archaeological nonsense

In the latest installment of Digging for Britain’s Season 11, the spotlight turns to the intriguing Caerfai Promontory Fort, also known as Penpleidiau, perched on the edge of Wales. Nestled approximately 1.3km southeast of St David’s, this archaeological site, with its formidable features, compels a reevaluation of traditional interpretations and invites us to question the prevailing coastal ‘Hill Fort’ narrative. (Caerfai promontory fort – archaeological nonsense)

Caerfai promontory fort
All the banks are in the wrong place for a ‘Fort’ – Caerfai promontory fort – archaeological nonsense

Caerfai’s setting is undeniably spectacular, occupying a visually dominant coastal promontory that extends around 500m into St Bride’s Bay. Enclosed by a combination of imposing ramparts and 20m high cliffs, this 0.5ha sub-rectangular headland has long been classified as a coastal ‘Hill Fort,’ primarily due to its defensive banks. However, delving into the archaeological details reveals a complex story that challenges established perceptions.

The archaeological logic behind categorising Caerfai as a ‘Hill Fort’ revolves around the presence of defensive banks, specifically the southern-most pair of parallel ramparts. These earthworks, enclosing the headland, are interrupted by two well-aligned gaps on the far eastern side, assumed to be entranceways. However, the flaw in this interpretation becomes apparent when examining the eastern sector, which interestingly lacks lidar maps, suggesting a belief that a substantial portion of land eroded into the sea to the west.

This erosion prompts questions about the strategic decision to fortify cliffs that already serve as a natural defense. The traditional archaeological logic suggests that the effort was taken to defend the interior, but the counterproductive nature of the higher banks to the north challenges the effectiveness of this defensive strategy.

Caerfai promontory fort
Lidar shows its not defensive – Caerfai promontory fort – archaeological nonsense

Moreover, the presence of clear remains of an external ditch associated with the large rampart adds another layer of complexity. This ditch runs from the western cliff-face, wrapping around the rampart’s eastern terminal. The ditch, around 1m deep along most of its length, is notably deeper in the east than the west, a feature that defies the expectations of a defensive structure. The inconsistency and continuation of the ditch beyond the banks raise questions about its intended purpose.

Challenging the traditional narrative, an alternative interpretation emerges—one that aligns more closely with the practical use of cross-dykes by boats during inclement weather. This alternative perspective suggests that the site served as a mooring point, where boats could be pulled up on ropes during adverse conditions and lowered back into the water when departing. This pragmatic function adds a new layer of understanding to Caerfai, emphasizing its potential as a hub for maritime activities.

This can be seen very clearly in our investigation into Offa’s Dyke where the promortory fort near Chepstow has a similar cross-dyke section that was once interpreted as a ‘defensive ditch’ – the problem is that it is the wrong way if it is defending against the Welsh – so can only have been a cross-dyke for boats to moor at the site.

Caerfai promontory fort - archaeological nonsense
Cross-dyke as is facing away from the Welsh!! -Caerfai promontory fort – archaeological nonsense

In conclusion, the Caerfai Promontory Fort challenges the conventional ‘Hill Fort’ narrative, urging archaeologists to reconsider the purposes of coastal structures. This case study highlights the importance of questioning established interpretations and exploring alternative perspectives in archaeological studies. By unraveling the complexities of Caerfai, we gain valuable insights into the practical functions that may have shaped our ancient landscapes, ultimately enriching our understanding of the past.

Further Reading

For information about British Prehistory, visit for the most extensive archaeology blogs and investigations collection, including modern LiDAR reports.  This site also includes extracts and articles from the Robert John Langdon Trilogy about Britain in the Prehistoric period, including titles such as The Stonehenge EnigmaDawn of the Lost Civilisation and the ultimate proof of Post Glacial Flooding and the landscape we see today.

Robert John Langdon has also created a YouTube web channel with over 100 investigations and video documentaries to support his classic trilogy (Prehistoric Britain). He has also released a collection of strange coincidences that he calls ‘13 Things that Don’t Make Sense in History’ and his recent discovery of a lost Stone Avenue at Avebury in Wiltshire called ‘Silbury Avenue – the Lost Stone Avenue’.

Langdon has also produced a series of ‘shorts’, which are extracts from his main body of books:

The Ancient Mariners

Stonehenge Built 8300 BCE

Old Sarum

Prehistoric Rivers

Dykes ditches and Earthworks

Echoes of Atlantis

Homo Superior

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