The Lost Island of Avalon – revealed

Using the most effective archaeological tool available today (LiDAR), we can peel back the landscape to show how it used to look and reveal the lost Island of Avalon.

Avalon, literally meaning “the isle of fruit [or apple] trees”; sometimes written Avallon or Avilion) is a legendary island featured in the Arthurian legend.  It first appears in Geoffrey of Monmouth’s 1136 Historia Regum Britanniae (“The History of the Kings of Britain”) as the place where King Arthur’s sword, Excalibur, was forged, and later as the place where Arthur was taken to recover from being gravely wounded at the Battle of Camlann.  Since then, the island has become a symbol of Arthurian mythology, similar to Arthur’s castle Camelot.

Avalon was associated with mystical practices and figures such as Morgan le Fay from an early date.  It is often identified as the former island of Glastonbury Tor, where the later English variant of the legend made the place where King Arthur was taken to his final rest.  However, some traditions hold that Arthur never really died and will lead his people against their enemies.  Many other alternative locations of Avalon have been claimed or proposed as well.

The legend has been associated with Glastonbury, particularly the Tor, but to date, the tale is about an island, which has led to speculation about other locations.  My ‘Post-Glacial Flooding Hypothesis’ has now brought this legend and the association with Glastonbury back to life, as our new LiDAR map of the Mesolithic to the Bronze Age landscape shows that this area was affected by the higher water table, which made Glastonbury an island.

We can now take you on a journey into the past, to when the mysterious Island of Avalon was a reality, not just a myth!

The Lost Island of Avalon — Re-examined Through Landscape Science

This is a journey through time across the prehistoric landscape of Glastonbury, re-examined through modern landscape science rather than legend. What emerges is not a mythical island, but a measurable, physical reality — one that only becomes visible once we abandon today’s drained and managed terrain and instead reconstruct the landscape as it existed under raised water levels following the last Ice Age.

Central to this re-evaluation is the recognition that rivers, floodplains, and groundwater tables in the early Holocene were significantly higher than they are today. This is not a local anomaly but a widespread post-glacial condition, driven by isostatic adjustment, saturated aquifers, and constrained drainage systems. When these factors are applied to the Somerset Levels, the result is unavoidable: Glastonbury stood as a true island, surrounded by water, marsh, and navigable channels.

At the heart of this island stood Glastonbury Tor, rising sharply above the wetlands as a natural landmark, while the lower ground around Glastonbury Abbey occupied the sheltered interior of the island itself. Together, these form the core of what later tradition remembered as the Isle of Avalon — not as myth, but as geography.

What has changed decisively since earlier studies is the availability of high-resolution LiDAR. Unlike conventional aerial photography or excavation-led interpretation, LiDAR strips away vegetation and modern land use to reveal the underlying terrain. Across the Somerset Levels, it exposes:

• fossil river channels
• submerged shorelines
• causeways and access routes
• isolated high ground consistent with island formation

When these features are mapped together, Avalon ceases to be symbolic. It becomes topographically inevitable.

This understanding aligns directly with broader evidence presented elsewhere in the Prehistoric Britain research, particularly the demonstration that many major prehistoric sites — including Stonehenge, Avebury, and Durrington Walls — were constructed with reference to waterborne landscapes, not dry farmland. The builders of these monuments were not reacting to myth or symbolism, but to hydrology, access, visibility, and control of movement.

Seen in this context, Avalon represents something far more important than later medieval storytelling. It is evidence that early societies understood and exploited flooded landscapes, selecting islands, peninsulas, and navigable wetlands as centres of activity long before later drainage erased the clues.

The problem has never been a lack of evidence — it has been a failure to reconstruct the correct landscape. With LiDAR and post-glacial hydrology now applied together, the Isle of Avalon no longer needs defending as legend. It stands revealed as a real place, in a real landscape, at a real point in time.

Author’s Biography

Robert John Langdon, a polymathic luminary, emerges as a writer, historian, and eminent specialist in LiDAR Landscape Archaeology.

His intellectual voyage has interwoven with stints as an astute scrutineer for governmental realms and grand corporate bastions, a tapestry spanning British Telecommunications, Cable and Wireless, British Gas, and the esteemed University of London.

A decade hence, Robert’s transition into retirement unfurled a chapter of insatiable curiosity. This phase saw him immerse himself in Politics, Archaeology, Philosophy, and the enigmatic realm of Quantum Mechanics. His academic odyssey traversed the venerable corridors of knowledge hubs such as the Museum of London, University College London, Birkbeck College, The City Literature Institute, and Chichester University.

In the symphony of his life, Robert is a custodian of three progeny and a pair of cherished grandchildren. His sanctuary lies ensconced in the embrace of West Wales, where he inhabits an isolated cottage, its windows framing a vista of the boundless sea – a retreat from the scrutinous gaze of the Her Majesty’s Revenue and Customs, an amiable clandestinity in the lap of nature’s embrace.

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.

Further Reading

For those interested in British Prehistory, visit www.prehistoric-britain.co.uk, a comprehensive resource featuring an extensive collection of archaeology articles, modern LiDAR investigations, and groundbreaking research. The site also includes insights and extracts from the acclaimed Robert John Langdon Trilogy, a series of books exploring Britain during the Prehistoric period. Titles in the trilogy include The Stonehenge Enigma, Dawn of the Lost Civilisation, and The Post Glacial Flooding Hypothesis, offering compelling evidence about ancient landscapes shaped by post-glacial flooding.

To further explore these topics, Robert John Langdon has developed a dedicated YouTube channel featuring over 100 video documentaries and investigations that complement the trilogy. Notable discoveries and studies showcased on the channel include 13 Things that Don’t Make Sense in History and the revelation of Silbury Avenue – The Lost Stone Avenue, a rediscovered prehistoric feature at Avebury, Wiltshire.

In addition to his main works, Langdon has released a series of shorter, accessible publications, ideal for readers delving into specific topics. These include:

• The Ancient Mariners
• Stonehenge Built 8300 BCE
• Old Sarum
• Prehistoric Rivers
• Dykes, Ditches, and Earthworks
• Echoes of Atlantis
• Homo Superior
• 13 Things that Don’t Make Sense in History
• Silbury Avenue – The Lost Stone Avenue
• Offa’s Dyke
• The Stonehenge Enigma
• The Post-Glacial Flooding Hypothesis
• The Stonehenge Hoax
• Dawn of the Lost Civilisation
• Darwin’s Children
• Great Chester’s Roman Aqueduct
• Wansdyke

For active discussions and updates on the trilogy’s findings and recent LiDAR investigations, join our vibrant community on Facebook. Engage with like-minded enthusiasts by leaving a message or contributing to debates in our Facebook Group.

Whether through the books, the website, or interactive videos, we aim to provide a deeper understanding of Britain’s fascinating prehistoric past. We encourage you to explore these resources and uncover the mysteries of ancient landscapes through the lens of modern archaeology.

For more information, including chapter extracts and related publications, visit the Robert John Langdon Author Page. Dive into works such as The Stonehenge Enigma or Dawn of the Lost Civilisation, and explore cutting-edge theories that challenge traditional historical narratives.

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