survey. Second, these earthworks were individually mapped using GPS. Third, visible ceramics on the surface of these earthworks were collected. Finally, the collected ceramics were described using a modal analysis. Caucasian ring ditches The analysis of CORONA satellite images, as well as satellite and aerial photos of the 1970s and 1980s, revealed more than thirty ring-shaped structures. Most of these structures are located between Stavropol and Pyatigorsk in northwestern Caucasus. The sites resemble circular ditches around a large central place without any sign of an entrance. The structures resemble the size and shape those of the well known Neolithic ring-ditches from Slovakia, Austria, Southern Bavaria and England. Walton Court ring ditch An excavation team determined the nature of the ring ditch located in Radnorshire's Walton Basin, near Walton Court Farm in September 2009. It was identified as a crop mark via aerial photography. The measurements of the ring ditch include a 100m diameter and a somewhat narrow ditch. This ring ditch is the largest site in mid and northeast Wales to date. The sections excavated allowed dating of the ring ditch but did not reveal any artifacts or archaeological evidence, with the exception of charcoal recovered from the base which was dated at 2570-2300 cal. BC. Notes External links http://www.cpat.org.uk/projects/longer/walcourt/walcourt.htm References Archaeological features Types of monuments and memorials