Historian debunks 'witches' marks' theory, says symbols are stonemasons' training marks

For years, visitors to medieval churches and grand barns across England have been told they were looking at witches' marks—carved symbols meant to ward off evil spirits and protect buildings from supernatural harm. English Heritage and Historic England have promoted this interpretation widely, identifying what they describe as ritual protection marks on hundreds of sites. But a leading architectural historian has now challenged this entire framework, arguing there is no historical basis for it whatsoever.

Jennifer Alexander, a professor of architectural history at Warwick University, says the symbols in question—particularly daisy wheels and hexafoils—are nothing more than the practical working marks of stonemasons and the training exercises of their apprentices. In 2024, English Heritage announced that Gainsborough Old Hall in Lincolnshire contained what it called "a staggering array" of these supposed ritual marks, the most ever identified at any of its 400 sites. The organization described circles, overlapping Vs, Marian marks invoking the Virgin Mary, and pentangles, all supposedly designed to trap demons or call for divine protection. But Alexander's interpretation is starkly different: these are the geometric doodles of people learning their craft.

"Do you remember at school when you were first given a pair of compasses and you made a daisy wheel?" Alexander asked in an interview. "It's that." She describes the marks as practical geometry lessons—apprentices practicing the fundamental skill of drawing circles and geometric patterns on stone using compasses and straight edges. The varying degrees of skill visible in the marks themselves support this reading. A poorly executed circle or an incomplete hexafoil isn't evidence of mystical intent; it's evidence of a learner struggling with the difficulty of drawing clean lines on an unforgiving surface like stone, where the angle of your wrist changes as you move around the circumference.

The barn at Bradford-on-Avon in Wiltshire, a 14th-century structure, illustrates Alexander's point. The walls there contain a huge number of designs of wildly varying skill levels. Alexander suggests the building may have served as a schoolroom or mason's training shop when it wasn't needed for storing farm produce. Some marks, she notes, are mason ciphers—letters like W or M that helped workers assemble stones in the correct order during construction or that identified whose work had been done. These are the marks of a practical trade, not a supernatural belief system.

Historic England has long acknowledged competing theories about these symbols. Its website notes that some scholars see hexafoils as sun motifs connected to Wicca, a contemporary pagan movement, while others suggest they are purely secular geometric exercises. But the organization has presented the "ritual protection mark" interpretation as "the most widely accepted theory at present." In 2016, Historic England even launched a public campaign asking people to hunt for witches' marks, framing them as evidence of historical belief in witchcraft and the supernatural.

Alexander is blunt about what she sees as a misreading of the evidence. "Anything on a stone building that looks like a design gets picked up as these damn things now," she said. "There's absolutely no evidence they were ever used" as protection symbols. Her new book, Stonemasons' Marks, published by Routledge, explores how these marks were actually used and what they reveal about medieval construction and the people who performed it. The work arrives as she presents her research at this week's International Medieval Congress in Leeds.

Both English Heritage and Historic England have responded diplomatically to Alexander's challenge. English Heritage said it welcomes debates that encourage fresh perspectives on the past. Historic England stated it welcomes new research that adds to understanding of these marks and enriches the picture of the people who made and used historic buildings. Neither organization has defended the witches' marks interpretation or suggested it will change how it presents these symbols to the public. What was once confidently identified as evidence of medieval superstition may turn out to be something far more mundane: the fingerprints of apprentices learning to use their tools.