Nash et al. 2026 / Quaternary
The red markings at Bacon Hole, thought to be a natural geological formation, are after all the oldest cave paintings in the British Isles, dating back 17,000 years.
For a century, a series of mysterious red lines found inside a cave in Wales were dismissed as a natural geological formation. Now, a new investigation has confirmed that the marks are paleolithic rock artmaking them the oldest known rock art in the British Isles.
The discovery concerns a panel of 11 parallel red lines located in Bacon Hole, a cave on the Gower Peninsula in southwest Wales. The markings were first identified in 1912 by geologists and archaeologists, who initially considered them to be the first known example of Upper Paleolithic rock art in Britain. However, skepticism arose in the following decades, and by the late 1920s many experts concluded that the lines were likely formed by natural processes.
The debate lost steam after the exact location of the panel inside the cave was lost. According to , this changed in 2022, when an international team of researchers rediscovered the work of art and carried out a detailed scientific analysis.
In a new one published in the journal Quaternary, researchers used uranium-thorium dating on a layer of calcite that formed over the engravings. The results indicate that the art was created between approximately 18,300 and 15,700 yearsplacing it firmly in the Upper Paleolithic and dating it to around 17,000 years old.
The team also analyzed the pigment and discovered that the red color came from hematitea mineral rich in iron naturally present in other parts of the cave. The researchers argue that the evenly spaced lines are probably not the product of natural forces. Instead, their regular arrangement suggests deliberate human creation. Additional evidence, including finger marks and splashes of pigment found in other parts of the cave, reinforce the interpretation of the site as a space for artistic activity.
The main author, George Nashan archaeologist at the University of Liverpool, said the cave may have had special significance for prehistoric communities. “The presence of rock art in the deepest, darkest parts of Bacon Hole suggests that at least some areas of the cave may have had symbolic or ritual meaning”, these.
Because the rock art is located in a section of the cave devoid of natural light, researchers believe the environment itself may have played an important role. “Darkness itself may have been an essential part of the ritual experience,” Nash explained, noting that deep cave chambers can appear isolated, mysterious, and separate from everyday life.
Bacon Hole continued to attract visitors long after the Paleolithic. Archaeologists have discovered Roman, Saxon, medieval and pre-Roman artifacts at the site, suggesting that it was remained culturally significant for thousands of years.
