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

► We identified hypothetical fortifications using remote sensing. ► In two coastal valleys in Peru we identified 173 remote and 58 field anomalies. ► We ground truthed 158 anomalies, and 140 were positive. ► Grouping these positive anomalies resulted in 82 fortifications. ► These results more than double the number of known fortifications in these valleys.