James Ford, Longleat’s curator, said: “The one at Longleat is very faint and difficult to see; it’s in a form known as a daisy wheel or hexafoil.
“These types of ritualistic symbols were added to buildings over the centuries as a way of warding off witches or evil spirits.
“They are often found by doors, windows or fireplaces, which were seen as weak points where evil could enter.”
They have been found on buildings from the medieval period to the early 1800s, and the one at Longleat is late example; carved below a window in the stable yard which was built in the 19th century.
Witches’ marks – also known as apotropaic markings – have been found in historic buildings across England; although many have faded and can easily be missed.
“As far as we are aware this is the only one at Longleat. Why the stable yard and not on any of the other historic buildings is not known; a mystery often debated at Halloween,” added James.
You can also find marks at Bradford-on-Avon Tithe Barn, Tisbury Tithe Barn and buildings on the Fonthill Estate.
Witchmark Distillery on the Fonthill Estate take their name from the marks. You can see the logo on their whisky.