monument, which consists of thousands of precisely aligned holes at Monte Sierpe, 220km south-east of Lima, as a place of trade, exchange and accounting. Its design may also mirror khipus, ancient Andean knotted-string record-keeping devices.

“Our findings are unexpected and carry implications for better understanding accounting, exchange and resource management within and beyond the Andes,” Jacob Bongers, lead author of the research paper and an archaeologist at the University of Sydney in Australia, tells The Art Newspaper. 

Stretching for 1.5km along a ridge of Peru’s Pisco Valley, and 14m to 22m wide, the site consists of around 5,200 aligned holes, each up to 2m in diameter and up to 1m in depth. 

Along the band, the holes are organised into around 60 sections separated by empty spaces. These sections can differ in their number of holes—one section has nine rows of eight holes, for example, while another has six rows of seven holes with a final row of eight.