The three blobs look like one of those pictures the Curiosity Rover sends back from Mars. The next image resembles the outline of a snail.

But these two photographs represent just the tip of a fascinating iceberg, discovered with a new radar technique, which has revealed more than 500 ancient sites the National Park Authority didn’t even know it had.

The images came about after the whole park was raked with LiDar (light and radar), a remote sensing technology deployed from a light aircraft.

Heritage and data mapping officer Lawrence Shaw, left, says: “The whole thing started in 2010 where a trial segment of the forest was subjected to LiDar to see how successful it would be in identifying and sourcing archaeological features in that area.”

Although completely harmless to humans and animals, LiDar is able to penetrate the vegetation and trees to reveal what features may lie beneath.

It was, says Lawrence, a great success, and on the back of it, the authority applied for a Higher Level Stewardship Scheme grant to fund a survey of the entire area, so far the biggest scheme of its kind in Europe.

The project still has seven years to run but already, says Lawrence, they have identified some amazing finds.

“We can only identify features which are extant, which means raised or indented, so we couldn’t identify a longship or something buried under the soil,” he says.

“But we can see features we would never have known were there.”

One of the standout finds is the outline of an Iron Age fort which has come to light in the north of the park. Resembling a 200-metre long snail, it’s important because it includes what Lawrence believes may be a ‘banjo’ enclosure to protect inhabitants or livestock.

“It’s well-preserved and to our knowledge, unique in the forest,” he says.

“It will improve our knowledge of life here during the Iron Age.”

The other impressive find is a Bronze Age barrow which, again, doesn’t look much until you understand the stories behind it which have been partly revealed by LiDar.

“The barrows were probably built around 2,000 BC,” says Lawrence.

“We noticed that one barrow had this rectangular shape on it and that threw up a bit of concern because the way the data’s collected, anything over a certain height gets chopped out.”

Deciding they needed to take a closer look, the heritage team discovered a mound sticking out of its side with trees and gorse growing on it.

“It started ringing warning bells because no barrow I’d ever seen had a lump like this on the side,” says Lawrence.

They used map progression – the study of historic Ordnance Survey maps – to see if they could establish what had happened.

“The first edition of the OS map showed five barrows on this site in 1869 but on the 1897 edition there were only three barrows,” says Lawrence.

They eventually discovered that a local rifle club had gone in between the two dates to use the disfigured barrow as a butt, or target.

“A history enthusiast dug up a letter from the Agisters to the rifle club saying that if they’d known they were going to damage the burial grounds, they would never have given them permission to use the forest for their shooting,” he says.

However, he added, there was even more to the story. During World War II, he says, there were fears that Germans would use the flat area around these barrows to land gliders for an invasion. “We noticed these additional lines on the LiDar and realised they’d made anti-glider obstacles, incorporating part of the damaged barrow,” he says.

As the project continues, more information will become available although, says Lawrence, it’s already being used to ensure the park doesn’t damage its new-found historic features. The LiDar maps are also available for visitors and residents to access on the park authority’s website so they can check out features near them, or ones they can visit on a walk.

“In Egypt they have used LiDar to discover lost empires,” says Lawrence.

“Now, in a way, we’re using it to find the lost New Forest empire.”

  • newforestnpa.gov.uk/heritagemapping

This feature appears in this weekend's Seven Days magazine inside your Daily Echo, see features, recipes, home ideas and lots more at bournemouthecho.co.uk/sevendays