Lasers Reveal Intriguing Bronze Age Monument Hidden In The Forest Of Dean


Rachel Baxter

Copy Editor & Staff Writer


Moss-covered rocks in Puzzlewood, part of the Forest of Dean in the UK. Fulcanelli/Shutterstock

The Forest of Dean, Harry and Hermione’s hideout and home of the so-called “bleeding stone”, has long been hiding a mysterious circular monument called a ring cairn. The remains of the monument, which dates back to the Bronze Age, have been revealed thanks to laser technology called LiDAR, a technique previously used to uncover thousands of Maya structures in the Guatemalan jungle, among other intriguing ancient structures.

A forest in Gloucestershire, England, situated between Oxford and South Wales, might not sound quite as exciting as a tropical jungle, but the find is certainly a fascinating one.


"It was very exciting. I was expecting to find quite a lot of new sites with the LiDAR, but nothing as interesting as this," archaeologist Jon Hoyle, who found the structure, told BBC News. He discusses the discovery in a new book called Hidden Landscapes of the Forest of Dean.

At first, Hoyle thought the monument might be a gun emplacement used during the Second World War but further study revealed that it was much, much older. The structure was likely created between 2,500 and 1,500 BCE, during the Bronze Age, a period of British history where bronze gradually replaced stone as the key material used to make tools.

LiDAR view of the ring cairn. Forestry Commission

We’re still not certain exactly what ring cairns were used for. They are circular, low embankments created using earth and stone. Graves have been found within certain ring cairns but it is thought that serving as burial grounds was not their main function. It is believed they were used ceremonially, and evidence of fire has been found within their perimeters.

The ring cairn in the Forest of Dean measures 25 meters (82 feet) across and incorporates at least 10 white limestone stones, rising a meter (3.3 feet) or less in height, BBC News reports. While these intriguing structures have previously been found in other counties in the UK, this is the first ever to be discovered in Gloucestershire. It lies in an undisclosed location, somewhere near the small village of Tidenham.


"Following a LiDAR survey carried out in the Forest of Dean in 2010, a circular feature was revealed amongst the trees," said a Forestry England spokesperson in a statement emailed to IFLScience. "Forestry Commission, now known as Forestry England, carefully cleared the site of trees and brambles at the time to uncover this Bronze Age relic. Since its discovery, we have carefully managed the site to ensure its preservation."

Without the help of LiDAR, which stands for Light Detection and Ranging, the find would still lie undiscovered amid the forest’s verdant undergrowth. The technology can map hidden structures by producing laser beams and measuring the light that bounces back. In recent years, the tech has been used to discover Cambodia’s hidden ancient city of Mahendraparvata, reveal secret tunnels of the Knights Templar, and uncover the remains of a sprawling ancient Maya megacity in the dense jungle of Central America.

[H/T: BBC News