Dorset's sunken paths to be mapped by Natural England

The scheme by Natural England seeks to map little-known sunken paths which are known as holloways.

The name holloways come from the old English word 'hola weg', meaning sunken road. These sunken lanes are common in the west country due to the underlying rock being soft sandstone.

Hell Lane and Shute's Lane, between Symondsbury and North Chideock, were the first to undergo mapping as part of the project.

Senior Advisor Citizen Science for Natural England Andy Jefferies, who lives near Bridport, said: "This is an exploratory project looking at the overall value of holloways; historically, ecologically and culturally.

"We chose to survey Hell Lane and Shute's Lane because they are some of the most impressive holloways there are."

A 3D laser scanner - usually used for building surveys - was placed at 258 survey points each five to ten meters apart. Each survey point alone captures between four to ten million data points, accurately surveying the hollow in 3D to a 5mm resolution.

Worn down over hundreds of years by the passage of feet, livestock and wagons; the weather also plays an important part in the formation of these lanes, the deep sides funnel the falling rain from the surrounding land which then pours down the narrow space.

Over the years many holloways have come to feature 'graffiti', with Hell and Shute Lanes having some of the best.

"They do have a lot of 'I was here' carved into them, but also gargoyle-like faces. I'm a scientist, but people pick up on something mysterious and mystical about holloways. They are like great inverted cathedrals" said Mr Jefferies.

This project aims to raise awareness of the holloways, not only as cultural and historical landmarks but also as ecologically important features.

Mr Jefferies added: "These holloways have an interesting ecological function connecting habitats and providing a safe space for nature. They provide fairly unusual habitats of exposed rock and have banks covered in moss and ivy. They are rich dark green places, and nobody knows the full extent of them in the UK."

The scanning of Hell and Shute lane wrapped up yesterday. In March the initial project will be completed, and Natural England will publish a report with the findings.

Natural England is inviting anyone who wants to help map holloways to share their findings and pictures on Twitter with #sunkenlanes.