Jorge Olano, Peruvian archaeologist and co-Director of the Research Programme on Lines and Geoglyphs, and the University of Yamagata in Japan, headed by Professor Masato Sakai, have been working since 2004 to identify the Nazca geoglyphs. Interview with this passionate researcher.

Japan. Geoglyph of a fish-like creature holding a shovel or knife. Yamagata University.
Peru. Geoglyph of a fish-like creature holding a shovel or knife. © Yamagata University.

How were ancient peoples able to create precise geoglyphs like the Nazca lines without being able to observe them from the sky?

Peru. Spiral Nazca geoglyph. Diego Delso/Commons.
Peru. Nazca geoglyph in the shape of a spiral. © Diego Delso/Commons.

The first thing to note is that the Pampa de Nazca is home to figures and lines of all shapes and sizes. Although the largest figures are the most famous, they are neither the most numerous nor the oldest. Thanks to the research carried out over the last few years by our team and others in different parts of the region, we now know that many figures have yet to be discovered in this territory. Most of them are small, measuring between 3 and 6 metres in length, and appear to be more numerous than the larger known figures. What's more, their iconography makes them look older. This shows that the creation of figures on the desert floor is a very ancient practice, which has evolved over time, both in terms of the techniques used and the dimensions and motifs represented. It is therefore impossible to fully understand the purpose and creation of the great figures without taking into account the evolution and transformations of this practice through the ages. Recent discoveries of new figures in the pampas are beginning to shed new light on this process.

Can these geoglyphs be dated?

Peru. Geoglyph of human form in the Nazca desert. Yamagata University.
Peru. New humanoid geoglyph in the Nazca desert ©. Yamagata University.

Over the years, several attempts have been made to date geoglyphs using different scientific techniques, but no conclusive method has yet been found. Currently, the most widely accepted method for estimating the period and chronology of a geoglyph is based on a comparison of the motifs with the iconography of the pre-Hispanic cultures that inhabited the region. These motifs appear on artefacts such as ceramics and textiles. Thanks to these comparisons, researchers generally believe that the large figures on the pampas are associated with the ancient Nazca period, chronologically situated between 50 and 300 AD.
On the other hand, the smaller figures, often drawn on hillsides or along roads, display iconography similar to that found in petroglyphs and textiles from the late Paracas era, dated between 150 and 50 BC.
Another approach to dating geoglyphs involves stylistic analysis of ceramics found on the surface of, near to or inside the marks. This method provides a valid reference for the period when the geoglyphs were used, but not necessarily for the period when they were created. In any case, the surface ceramics documented by our recent research seem to confirm that the Nazca period corresponds to the phase of greatest activity in the use of geoglyphs. As for the smaller figures executed on the slopes of the hills, they are still poorly understood, partly because no material remains are generally associated with them.

How many lines have been identified to date?

Peru. New geoglyph discovered at Nazca thanks to AI. Yamagata University.
Peru. New geoglyph discovered at Nazca thanks to AI. © Yamagata University.


The most common geoglyphs in the Pampas are straight lines and trapezoidal shapes. There are thousands of these motifs, but their exact number is still unknown. On the other hand, for geoglyphs representing animal, human and other forms, the current count stands at around 430, of which almost 318 have been discovered thanks to our research.

What could these mysterious lines have been used for? What are your hypotheses (astronomy, rituals, etc.)?

Peru. One of the new geoglyphs discovered at Nazca by the Yamagata University team is that of a figure wearing a sort of crown. Yamagata University.
Peru. Among the new geoglyphs discovered at Nazca by the Yamagata University team is one of a figure wearing a sort of crown. © Yamagata University.

The giant linear figurative geoglyphs mainly represent wild animals. They are scattered along a complex network of linear and trapezoidal geoglyphs, indicating that they were probably created and used as part of ritual activities on a community scale.
The small geoglyphs mainly represent human motifs or elements modified by man, such as domestic animals and decapitated heads. They are generally located near the winding paths that cross the pampas, and were probably made by individuals or small groups. These geoglyphs appear to have been designed as 'signs' or 'markers', visible from the paths, to convey information about human activities, particularly those related to domestic animals and decapitated heads.

What research are you currently carrying out in Peru with the help of AI?

Peru. Large Nazca geoglyph. Nikola/Commons.
Peru. Large Nazca geoglyph © Nikola/Commons.

The Nazca Pampa covers a vast area of 450 square kilometres, making prospecting on foot and manual analysis of all the high-resolution aerial images particularly time-consuming and costly. Using artificial intelligence, we were able to analyse a large amount of geospatial data provided by aircraft to identify priority areas likely to contain geoglyphs. Over the past year, this approach has considerably accelerated the process of detecting geoglyphs and improved our understanding of their characteristics and distribution. This research is the result of a collaboration between Yamagata University's Nazca Institute and IBM Research.