For thousands of years, people lived and worked on the ridge of Mynydd Preseli. The earliest evidence dates to the Mesolithic period, 8,000 years ago, but this area is famous for its Neolithic use, between 4,500 years ago, when spotted dolerite, or Preseli Bluestone, was transported to Wiltshire and used at Stonehenge.
In the Bronze Age, about 4,300 years ago, round barrows or burial mounds were built. In upland areas, round barrows were built mainly of stone while in lowland areas, earth was used. Both types were used as resting places for the dead and their grave goods.
During the Iron Age, 2,700-2,000 years ago, two hillforts were constructed at the eastern end of the ridge. Hillforts are defended enclosures surrounded by one or more walls, but vary in appearance, size, and usage. Foel Drygarn is one of the largest in west Wales, featuring over 270 platforms where roundhouses stood. Carn Alw hillfort is smaller and better defended, displaying a chevaux-de-frise, hundreds of upright stones designed to make approaching the hillfort harder.
The use of the ridgeway during the Romano-British period, from 2,000 years ago, is heavily debated. Some suggest that there was a road connecting the coast to the inland for trade, making use of earlier prehistoric trackways.
Since the medieval period, about 900 years ago, this land has been used for grazing animals, with evidence of enclosures, shepherd huts, settlements, and small-scale quarrying of rock outcrops found in the area.