They are a feature of ancient field systems such as the Celtic fields of the British Isles. Some opinions believe that they were passively formed under the long-term action of gravity and weathering on the loosened soil of a ploughed slope, while others believe they may have been intentionally formed, to prevent erosion and slippage of the ploughed slope.
The archaeology of the Sussex landscape.(The archaeology of Sussex to AD 2000)(Downland Settlement and Land-Use: The Archaeology of the Brighton Bypass)(Book Review)
Sep 01, 2005; DAVID RUDLING. (ed The archaeology of Sussex to AD 2000. vi+262 pages, 149 figures, 10 tables. 2003. King's Lynn: Heritage...