Ground truthing of remotely identified fortifications on the Central Coast of Perú

Abstract

Remote imagery, including freely available satellite images viewed in Google Earth® and historic aerial photographs, was used to identify anomalies in a 25,000 km2 macroregion encompassing 13 river valleys along the Peruvian coast. These anomalies, located atop hills and mountains, were hypothesized prehispanic fortifications. A sample of remotely identified anomalies was ground truthed in the Huaura and Fortaleza Valleys on the Central Coast of Perú. 140 positive anomalies were documented and assessed using a simple defensibility index. Our results significantly increase the number of fortifications identified in both valleys. We demonstrate the efficacy of this method for locating fortifications in a very large region to facilitate the systematic documentation of these durable indicators of warfare