During the last Ice Age most of western Herefordshire was covered by a thick layer of ice that had advanced from the north and west.

As this ice melted away it left behind many features of a once glaciated landscape, especially to the west of Hereford. These features include many hundreds of ponds.

This is how the western parts of Herefordshire may have looked around 25,000 years ago, when the last Ice Age was at its peak.

Higher areas would have protruted above the ice. These are called nunataks.

The ice cover would have extended westward into Wales and out into the Irish Sea.

Most of the Ice Age ponds have formed in depressions in the land surface formed by melting of ice – these are known as kettle holes.

The pictures shows kettle holes located close to an area of melting ice.
Over time the kettle holes become partially infilled with peat and sediments and become a micro-ecosystem supporting many unusual plants and animals.

Glacier containing boulders and smaller rock debris embedded in the ice and beneath it.

As the glacier retreats in a warmimg climate a block of ice is left behind, insulated by an overburden of debris dumped as the main sheet of ice melts.

Glacier is gone, with buried ice block slowly melting.

Location of the former ice block is now a depression filled with water. Glacial debris will infill part of the hole.

The depression will slowly infill with washed in sediment and the formation of peat, from decayed vegetation that has become established in the glacial deposits.