Original: The construction of the earliest earthwork sites in Britain began during the early Neolithic (c. 4400 BC   3300 BC) in the form of long barrows used for communal burial and the first causewayed enclosures, sites which have parallels on the continent.
Simplified: The construction of the earliest earthwork sites in Britain began during the early Neolithic (c. 4400 BC- 3300 BC) in the form of long barrows used for communal burial.