'X-ray' scan of Wellhead, in Bourne, reveals 'amazing results' on importance of lost medieval castle

A geological survey has shed new light on the importance of a lost medieval castle in Bourne.

Steve Guillari stepped up his lifelong fascination with the castle into a programme of research about four years ago, supported by fellow members of Bourne History Group.

With the help of Grantham Archaeological Group, Steve and fellow volunteers carried out an earth resistance survey on the Wellhead earlier this month - the site of the Norman castle.

This kind of survey use probes inserted into the ground to provide an x-ray of the ground without the need for digging.

Layered on top of aerial photos and existing evidence, it showed up the inner and outer walls.

“The results are absolutely amazing," Steve said.

“We can now see it was a double-walled castle, known as a concentric castle.

"That has blown my mind because they were important castles.

“If someone had been able to break through the first defence they would find themselves stuck between two walls.

“It shows just how important the people who lived there saw themselves."

Also of interest is the outline of a bridge to the north of the castle.

Above ground, an enclosed mound, and inner and outer moats are all that can be seen today of the castle, built by Baldwin Fitzgilbert.

Steve added: "We knew where the original gatehouse was which came up in the first survey of 2006, but we now know there was an entrance to the north of the castle as well.

"I believe it would have been added later on."

As part of his research Steve looked back to a previous survey in 2006, along with other evidence gathered piecemeal over the years.

“When you put them all together it gives you a clearer picture," he explained.

“None of the information on Bourne Castle has ever been put in one place - it's all over the place.

"It’s a big, big puzzle we are solving.

“But because we know the castle is inches beneath our feet we don't have to look too far."

And more discoveries could soon be added to this evolving story.

A further survey was to be carried out this week on the northern part of the site.

The work seems to have captured the imagination within the town.

"The interest we have had from Bourne has been out of this world," Steve added.

"We have pretty much done the main area of the castle, so we are now looking at the outer bailey and want to find out more on what was outside the castle walls.

"During the Civil War, barracks may well have been built there as well."