Image by ….Tim
Sarsen stones are stone blocks found in quantity on Salisbury Plain, the Marlborough Downs, in Kent, and in smaller quantities in Berkshire, Oxfordshire, Dorset and Hampshire. They are the remains of a cap of tertiary sandstone which once covered much of southern England. It is a dense, hard rock created from sand bound by a silica cement, making it a kind of silicified sandstone.
Natural sarsen boulders created by glacial and periglacial effects can be sometimes found scattered on the ground surface, moved by solifluction; the stone is also present in surviving outcrops of the rock.
The builders of Stonehenge, Avebury and many other megalithic monuments in southern England chose to build with sarsen stones.
The stone in this shot make up part of the structure at the entrance to West Kennet Long Barrow.
West Kennet Long Barrow is one of the many prehistoric monuments that are part of the Avebury complex of Neolithic sites. It is one of the most impressive and well-preserved burial chambers in Britain, as well as being one of the most visited.
The tomb is thought to have been constructed around 3500BC, and was in use for a thousand years, until 2200BC, when the tomb was sealed with chalk rubble, and the gigantic sarcen boulders that now guard the entrance. This was at the same time as the great stone circle at Avebury was begun, and may signify a change in the focus of belief and religion.