SOME of Dorset's most ancient monuments have deteriorated badly over the last 40 years.

Details will be given tomorrow when a three-year South Dorset Ridgeway project, backed with £150,000 worth of Heritage Lottery Fund cash, is launched at Portesham Village Hall.

The Dorset Area of Outstanding Natural Beauty (AONB) team will be working with the fund and a team of local partners to put this special area on the map over the next three years.

Part of the launch will see English Heritage give news about their 2007 survey of the Ridgeway which was the most detailed for almost 40 years.

AONB spokesman Tom Munro said: "They found that a lot of Stone Age monuments had deteriorated quite badly.

"This was because of erosion and changes in agricultural practice which has left a number of sites, particularly long barrows in remote locations along the higher Ridgeway, in urgent need of preservation.

"English Heritage will talk about how to achieve that and all our hopes for the Ridgeway project at its launch in Portesham Village Hall."

Helping that launch will be television star Phil Harding of Channel 4's popular archaeology programme Time Team.

He will be in the hall demonstrating the art of flint knapping to underline South Dorset Ridgeway's incredible wealth of prehistoric remains.

Mr Harding said: "This area is very close to my heart. I worked on the flints from excavations there in the 1980s. It's an area bursting with exciting archaeological remains and enjoyably just a very beautiful place to be.

"The project will be a wonderful springboard to promote this landscape and make people aware of its special importance as an area of study and recreation."

He will be joined at the launch by artists and other archaeologists while John Walker will be talking about the landscape from an artist's perspective.