Solving the mystery of Egg Rock

Tŵr Gweno / Egg Rock, on the coast between Aberystwyth and Llanrhystud, was a local landmark and popular tourist attraction in Victorian times. Its disappearance more than a century ago is evidence of our constantly changing coastline but the date of its demise has been a mystery until now, as explained in this article to mark International Geomorphology Week 2025 (3-8 March).

The piece has been written by researchers Professor Stephen Tooth from our Department of Geography and Earth Sciences at Aberystwyth University, and Courtney Goode, who recently graduated with a Master’s degree in Environmental Change, Impact and Adaptation.

Over the last few decades, we have become increasingly aware that the world’s environment is changing. Recent years have been some of the warmest on record, sea levels continue to rise, and habitats and species are being lost at ever increasing rates.  Disasters such as heatwaves and droughts, catastrophic flash floods, and devastating wildfires seem to be occurring more often. 

Ceredigion is not subject to such extreme disasters.  Nevertheless, it is not immune from change, especially along its coastline, which perhaps can be regarded as being at the ‘frontline’ of environmental changes.

Geomorphology is the science that studies the origin and development of landforms — such as mountains, valleys, sand dunes and caves — and how those landforms combine to form landscapes. 

As local geomorphologists working with colleagues at Aberystwyth University and in the local community, we are particularly interested in how rapidly change has been occurring to rocky landforms along the Ceredigion coastline over the last 150 years. 

Visual archival materials – including geological sketches, paintings, and early photographs – have provided some invaluable lines of evidence, and helped to solve a few local mysteries.

For example, uncertainty has surrounded the timing of disappearance of a former coastal stack – known as Tŵr Gweno/Egg Rock – which was a well-known Victorian tourist attraction. 


Painting of Tŵr Gweno / Egg Rock by Alfred Worthington. Photo Credit: From the collections of Amgueddfa Ceredigion Museum.

 

Along with Alfred Worthington’s painting from around the turn of the last century, which is on display in Amgueddfa Ceredigion Museum, a number of photographs from the late 1800s and early 1900s show this landform in various stages of erosion, including the image shown alongside this article (from the collections of the National Monuments Record of Wales: David John Saer Album).

We can arrange the photographs in order based on the changing size and shape of Tŵr Gweno/Egg Rock, and compare the timeline with local newspaper reports highlighting its gradual demise owing to wave attack. As a result, we can say with confidence that the landform was lost in a coastal storm in 1907. By comparing the remaining coastal features with more recent photographs, we can also find the former location of Tŵr Gweno/Egg Rock.

Similar approaches are being taken to reconstruct the development of other local coastal landforms, including: Craig y Delyn/Harp Rock, south of Borth; Craig y Fulfran/Cormorant Rock and Allt Wen near Aberystwyth; and Twll Twrw/Monk’s Cave near the former Tŵr Gweno/Egg Rock. Over recent decades, the size and shape of Craig y Delyn/Harp Rock and Twll Twrw/Monk’s Cave have been changing dramatically, but other landforms have been changing in more subtle ways.

More research needs to be done to establish the patterns of change along this dynamic coastline. Each year, International Geomorphology Week is celebrated in early March, with the aim of promoting geomorphological studies and mobilising the geomorphological community. 

As part of our contribution, we appeal to anyone with sketches, paintings or photographs of the local coastline to contact us.  Most useful are images of specific coastal landforms that are at least 10 years old, particularly if taken from locations that can be easily identified and revisited.  Use of visual archival materials to reconstruct coastal landform changes provides a valuable historical perspective that can complement shorter term monitoring of change using advanced technology, such as drone surveys.

We are grateful to the National Monuments Record of Wales: David John Saer Album Collection, and to Amgueddfa Ceredigion Museum for allowing us to use images of Egg Rock from their collections. Any readers who would like to share their photographs of our changing coastline can send them to Professor Stephen Tooth: set@aber.ac.uk.