EXPERIENCED abseilers have been roped in by English Heritage to help assess the condition of 34 ancient buildings.

Yesterday, surveying work got under way at Byland Abbey, near Thirsk, North Yorkshire, with climbers from the Herefordshire company, Wallwalkers, looking for signs of erosion on the masonry and clearing vegetation at high levels.

The abbey was founded in 1177 and is one of the North's great Cistercian monasteries.

The work is part of a study by English Heritage into historic sites under its guardianship in the Yorkshire and Humber region.

Condition surveys are carried out every four years so conservationists can plan repairs on properties such as Byland and Rievaulx abbeys and Scarborough Castle, so they can withstand the ravages of time.

English Heritage has turned to the abseilers to help inspect stonework which can be up to 100ft off the ground.

In the past, this has involved the use of unsightly scaffolding.

The abseilers take video and camera equipment to photograph the state of the masonry.

English Heritage works manager John Ward said: "Cameras will pinpoint where masonry needs attention. We'll combine this information with the results of fieldwork by our architects and building surveyors on the ground.

"That will give us a detailed picture, allowing us to plan ahead, keep monuments in good shape and ensure they are safe for the public to visit."