Legend has it Dorothy Beaumont was denied dying wish to be buried next to her daughter

It is said to be the spirit of a woman who died in child birth along with baby

They took the picture on a mobile phone from the top of the historic castle

Couple believe they have captured an image of the fabled 'Grey Lady ghost'

Pictures from the day trip revealed ghostly image of woman dressed in grey

She is, without a shadow of doubt, the most famous ghost at one of Britain’s most haunted sites.

But does this murky photograph show the fabled Grey Lady of Dudley Castle or something less spooky?

The image was taken by Amy Harper, 28, on her smartphone during a visit to the castle – which dates back to 1071 – with her husband Dean, 33, and their three children.

It was only when they were back home in Birmingham that Mrs Harper took a closer look.

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Creepy: Dean and Amy Harper believe their picture (close up right and circled left in yellow) shows the 'Grey Lady' who has supposedly haunted Dudley Castle in the West Midlands for centuries

The blurred close-up appears to show the outline of a woman with black hair dressed in grey robes standing next to a girl in an archway in the Sharington Range, pictured

She zoomed in on the picture, taken from the castle tower, of Sharington Range, a ruined Tudor building in the grounds.

Suddenly, she saw a hazy image of a woman in grey standing inside the arch.

‘It is really creepy,’ said Mrs Harper. ‘Dean had heard about the ghost of the Grey Lady and we think it must be her.’ The photo sparked speculation on social media that it was either the result of clever editing or had been achieved by using a special app that can implant ghoulish figures into images.

But Mrs Harper denied the suggestion, insisting: ‘To be honest I wouldn’t have a clue where to start.’

Barri Ghai, lead investigator at the Ghostfinder Paranormal Society, who call themselves the UK’s leading ghosthunters, said the figure is ‘too vague and grainy’ to be a hoax.

He believes the image may be the result of ‘matrixing’, a term increasingly used among paranormal investigators to describe the human mind’s natural tendency to find something familiar in complex shapes or colours. This can cause the brain to think it can see a specific person.

Amy Harper, pictured with her children Maycey, nine, Georgie, six and Scarlett, four, captured the chilling image on her mobile phone on a day trip to Dudley Castle

Mr Ghai, whose team has appeared in television shows in the UK, US and Japan, said that in the case of the Grey Lady, the shadows and light in the arch, combined with knowledge of the ghost’s fable, make us see what we want to see.

Matrixing may also help explain why people think they can see faces or symbols, for example, in clouds or burnt into a piece of toast. But Mr Ghai said there could also be the far simpler explanation for the Grey Lady’s appearance – that someone happened to be standing in the shadows when the photo was taken.

Whatever the explanation, the photograph, which was taken in August, is only now creating a stir among ghosthunters – just in time for the Hallowe’en season.