Mesolithic

At the end of the last glaciation the sea level was low because vast amounts of water was locked up in the glaciers.

Around 15 000 BC temperatures began to increase which led to the reoccupation of Britain from the continent as the ice sheets retreated. As the climate got warmer pine and birch forests became established and widespread.

By 8 000 BC most of Britain was covered in forest up to a tree line of 2 000 feet or more and so it is likely that by this period most of Pembrokeshire was wooded.

The increase in temperature led to the unlocking of large quantities of water from the melting ice sheets and consequently a rise in sea level leading to the flooding of large areas of forest.

The great herds of large animals which had been hunted by Palaeolithic man could not live in such a heavily wooded environment. They were forced to move to their natural habitat the cooler open plains that still existed further north. These animals were replaced by smaller ones more suited to the new conditions such as Roe and Fallow Deer and wild pigs.These changes meant that people had to adapt to their new environment and develop new hunting strategy.

Flint tools became much smaller because of the need to hunt smaller prey which were shot with bow and arrow, a weapon suited to the heavily wooded environment. Arrows were tipped with small sharp flint blades known as microliths.

Microliths were not only used in this capacity but were probably a multi-purpose tool used in a variety of ways. It is the appearance of these new tools that mark the beginning of the Mesolithic ( or Middle Stone Age ) period.

People, it appears, lived near the coast ,on rivers and lake sides where food was abundant, perhaps venturing inland seasonally for other food supplies.

Pembrokeshire is rich in finds dating from the Mesolithic period. Flint tools and waste flakes are found all around the present coast line, especially in the south of the county. Diligent searchers are also beginning to find scatters of Mesolithic tools inland.

It is likely that Pembrokeshire had a particularly favourable climate at this time and therefore a good supply of food would have been available throughout the year. This would explain why there are so many Mesolithic sites have been discovered in Pembrokeshire and so few elsewhere in Wales.

While some of the hunter gathers continued to live in caves, like Nanna's Cave on Caldey, others settled on coastal sites, within reach of the sea for fishing and for raw material in the shape of flint pebbles.