Banc y Celyn, Brecknockshire - Royal Commission on the Ancient ...

Uplands Initiative – <strong>Banc</strong> y <strong>Celyn</strong> 20082.2 Value of AP mapping to the field projectThe RCAHMW supplied interpretation of aerial photographs as digital files, referred toas AP mapping in this report. Each of these was investigated in the field, see Figure 7.231 separate records were supplied by the RCAHMW with the AP mapping (these arelisted in Appendix D). 2 of these were found to be outside the study area. 96 werefound to be identifiable archaeological features on the ground and given NPRNs. Theseincluded earthwork banks, cultivation marks, enclosures, leats, various mounds,quarries and trackways and a small number of settlement sites.Many of the remaining 133 records supplied by the RCAHMW were found to be linearfeatures such as sheep tracks or tracks made by modern farm vehicles, as well as thebraiding of existing trackways. The continuing practice of bracken cutting alsoproduces linear features which, viewed from the air, bear similarity to ridge and furrowcultivation. 42 of the AP features were found to have been caused by bracken cutting orother modern agricultural activity. 28 AP features were found to be natural orvegetational features, whilst 31 could not be identified on the ground at all.It is worth noting that many linear features such as leats and enclosure boundaries recordedon the ground were not picked up by AP mapping. More significant monuments such asplatforms and funerary cairns were also not identified from AP sources. Overall, APmapping, proved to be of some benefit during fieldwork, but the fact that the majority offeatures identified proved not to be of archaeological interest, and the need for groundsurvey to identify some of the most important and characteristic upland monument types arereminders of the limitations of the use of aerial photography in some upland environments.Plate 9: The snows of February 2009 were of assistance in identifying cultivation marks, asseen here associated with Bank NPRN 247234. These are not visible on AP mapping23