In the desert of southern Peru lies a gigantic mystery, the evidence of which is spread out across roughly 190 sq miles of arid desert between the Inca and Nazca valleys, located some 200 miles south of the capital Lima. This elongated plain, known as the Pampas de Jumana, is nearly 40 miles long, and is criss-crossed by long, man-made lines that have cut a diverse variety of different figures and shapes into the earth. The lines appear to have been formed by brushing away a top layer of reddish, iron oxidecovered pebbles to reveal white sand beneath. Because the sand contains lime that hardens in the morning mists, the lines have been protected from erosion for several centuries. It has also helped that the desert plateau possesses a uniquely dry and windless climate. The figures are strange and puzzling, and have been broadly classified into two generic types: biomorphs and geoglyphs.

The biomorphs comprise around 70 representations of humans, animals and plants, including a whale, a fish, a spider, a jaguar, a hummingbird, a monkey and a pelican. The human shapes are stylised; to modern eyes some appear to be astronauts. There are also outlines of trees and flowers. The number of geoglyphs is even greater: there are around 900 different geometric forms and shapes, including straight lines, triangles, spirals and trapezoids. The scale of both types of shapes is gigantic. The pelican, for example, is approximately 300 metres in length. One of the straight lines runs without any deviation across the plain for nine miles.

The mystery – to put it simply – is this: who made these figures, and why? How were they made? What were they for? And why were they cut into the earth on such a gigantic scale?

The Discovey

Little is known about the lines, but there are records discussing them that date back to the 16th century: they are mentioned briefly in the chronicles of Pedro Cieza de León, a Spanish conquistador who published his observations in 1553. He appears however to have been unaware of the full extent of the figures, and to have concluded they were no more than trail markers.

The lines then were largely forgotten for the next three and a half centuries, until Toribio Mejía Xesspe, a Peruvian archaeologist, noticed them when hiking through the foothills in 1927. In the 1930s the development of regular commercial flights between Lima and Arequipa made the shapes visible to those travelling over them by air. In 1939 Paul Kosok, a Long Island University professor who was researching preInca irrigation systems, flew over the Nazca Lines and was able to make out the shape of a bird.

Competing Theories

Kosok was the first of a long line of international and Peruvian scholars who have struggled to explain the mystery, and come up with a range of competing theories, which go from the well-researched through to the imaginative, the somewhat improbable and the simply far-fetched. Fascinated by the scale of the giant figures and the fact that they seem to be best viewed from the air, Swiss writer Erich Von Daniken argued that they were in fact giant runways built to allow aliens to land on Earth. Von Daniken’s books, including best-seller “The Chariots of the Gods?”, written in 1968, have had a cult following for a number of years. However, the works are dismissed by most researchers as little more than science fiction.

Another writer, Jim Woodman, has argued that the figures could only have been drawn into the ground with someone up in the air overseeing the work and giving instructions. To try and prove his theory he built a hot-air balloon, using only materials that would have been available to the indigenous inhabitants of the region many centuries ago. While he managed to get his device airborne for two minutes, few were convinced by the experiment.

Kosok’s theory, developed with María Reiche, a German mathematician and archaeologist, seemed more probable. They argued that the figures were aligned with the stars, and that the plain was in fact “the largest astronomy book in the world”.

However, research in the 1960s by US astronomer Gerald Hawkins appears to have ruled this out. Hawkins used a computer programme to compare the lines with the position of important astronomical events centuries ago, but concluded that there was no significant correlation between celestial bodies and the figures in the desert.

More recent research has focused on the ancient cultures that lived in the region. The Paraca and the Nazca civilisations that succeeded them inhabited the valley for centuries. It is thought that the Paracas were responsible for the biomorphs that were probably made around 200 BC, with the Nazcas making the geoglyphs roughly 500 years later. The designs are visible from foothills throughout the valley and the idea that they can only be seen from aerial positions has been challenged as incorrect.

Investigators have argued that the Nazca could have used simple design and building techniques. For example, positioning two wooden stakes at a distance, and aligning a third with the first two at a further distance, provides a rudimentary but effective way of plotting a straight line at great distance.

Some stakes have, in fact, been found near the lines. Carbon dating techniques suggest they were used sometime between 400 CE and 650 CE. It has also been suggested that the Nazca had mastered a system for projecting small-scale designs onto the plains. Joe Nickell, a professor at University of Kentucky, has shown how this might have been done using ropes, wood sticks and lime.

Religious Symbolism

A growing body of evidence suggests the lines were connected to the religious belief systems of the local communities, and above all to water and fertility. While the plain is extremely dry, around 10 rivers that descend from the Andes criss-crossed it, offering a promising but precarious spot for the development of human settlement, rather like the Nile Delta in Egypt. Despite the volatile micro-climate, the Nazca lived in the plain for around eight centuries. In today’s terms the Nazca had to be very eco-friendly, carefully preserving water for agriculture and recycling their garbage as building materials. They developed horizontal wells in the foothills that tapped into the sloping water table. The sites of these wells, called puquios, seem to correlate with some of the lines.

Since 1997 a Peruvian-German collaborative research initiative, known as the Nazca-Palpa project, has been working on what could be called the religious dimension. One of its directors, Markus Reindel, said that walking the lines became a ritual.

“Our idea is that they were not meant as images to be seen anymore, but stages to be walked on, to be used for religious ceremonies,” Reindel said. A number of shrines along the lines have been discovered, some containing sea-shell offerings known to be symbols of water and fertility. There may have also been sacred mountains worshipped as deities.

In 2004 archaeologist Cristina Conlee discovered a headless skeleton at a site called La Tiza in the southern Nazca region. It appears to have belonged to a young Nazca man; beside it was a decorated ceramic container known as a head jar. “Although we find trophy heads spread throughout the Nazca period, there are some indications that they became more common in the middle and late period, and at times of environmental stress, perhaps drought,” Conlee told the National Geographic. “If this was a sacrifice, it was made to appease the gods, perhaps because of a drought or crop failure,” he added.

Researchers believe that around the sixth century CE, increasing aridity led to the collapse of the Nazca culture. Water seems to have been scarcer in some valleys than others, and the leaders of different valleys may have been in conflict. By 650 CE a new and more militaristic civilisation, the Huari, had begun to expand from the central highlands displacing the remnants of the southern Nazca.

In Peril

The Nazca lines were designated a World Heritage site by UNESCO in 1994. The UN body described them “a unique and magnificent artistic achievement that is unrivalled in it dimensions and diversity anywhere in the pre-historic world”. Ironically perhaps, given their longevity, there are now worries that they may be under threat.

Viktoria Nikitzki of the Maria Reiche Centre has warned that “there has been deforestation everywhere so water from the highlands comes down to the Lines in streams and rivers. The Lines themselves are superficial; they are only 10-30cm deep and could be washed away. There is no maintenance or any sort of care for the Lines”.

The weather also poses a threat. Nazca has only ever received a small amount of rain, but changing weather patters have raised the risks from heavy rainfall, which could permanently damage the Lines. In 2014 high winds and sandstorms revealed undiscovered shapes, including a 60-metre long snake.