Three hundred million years ago this area was part of a vast delta.

The water carried particles from eroded rocks to the north. Sand settled from shallow slow-moving water and mud from deeper water. Plants and animals died, were covered and fossilised.

As the deposits accumulated, compression and heat transformed them into layers of sandstone and shale. For the next few hundred years, the rocks were eroded by ice and water. Ten thousand years ago, after the last Ice Age, forests of Pine, Oak and Birch covered the area. Their remains can still be found preserved in the peat.

About seven thousand years ago, the climate became cooler and wetter, the trees died, peat started to accumulate and it now covers most of the moor in a thick blanket. The moor is a mosaic of habitats from moires to dry grassland, each with its own species adapted to the particular conditions.

This variety of habitats is essential to the support of several species of bird which breed on the moor, some of which are of international importance.

In the last few hundred years, pollution, overgrazing and fire have damaged the moor by reducing the number of plant species and exposing areas of peat which rapidly erode. This bare peat does not easily regenerate the plants that once grew there. Here the National Trust must intervene by fencing off areas and reseeding with heather or grasses.

Although the National Trust’s principal task is to halt further erosion of the peat, we are also replanting trees in some of the cloughs and controlling the spread of bracken. A survey of the present condition of the moor is underway so that in years to come it will be possible to determine how the moor is changing.