I learned this today. The Nazca lines were made using wooden stakes and ropes to make them straight. Then the top layer of soil was removed.
How the Nazca lines were made is an easier question to answer than why they were made. First of all, let’s look at what the Nazca lines actually are.
The Nazca lines are a collection of enormous geoglyphs drawn on the ground. They are dug into the floor of the Nazca desert, which is in Peru, about 400 km south of Lima. There are 800 straight lines, 300 geometric figures, and 70 animal and plant designs. The shapes cover an area of 50 km2 and the lines cover an area of 450km2. The longest line is 48 km long.
The lines were created between 500 BC and 500 AD. They were created by two different groups of people. The first group were the Paracas people and they dug lines between 500 BC and 200 BC. The second group were the Nazca people and they dug lines from 200 BC to 500 AD.
The Paracus people were an Andean society that lived in the modern Ica Region of Peru. They appeared in about 800 BC and had disappeared by about 100 BC. They were experts in irrigation and water management. That was a useful skill because the Nazca desert is one of the driest deserts on Earth. They were also skilled in textile arts. The Nazca people appeared in about 100 BC and seem to have evolved from the Paracus people. Another group of people, called the Topara culture, invaded the Paracus region in about 150 BC. These two cultures lived together for a while and it is possible that this gave rise to the Nazca people. The Nazca culture began to decline in 500 AD (about when they stopped making the geoglyphs) and they had disappeared by 750.
So, how did they make the Nazca lines? The Nazca desert is covered in reddish-brown, iron-oxide coated pebbles. It looks a bit like the surface of Mars. The Paracus and the Nazca people made the lines by removing these red pebbles and digging a trench down to the lighter colored clay earth underneath. The light earth creates a sharp contrast with the surface coloring of the desert and makes the lines very visible.
The people who made the lines were helped by two natural phenomena. The first is that the earth at the bottom of the trenches contains a high amount of lime. The desert is extremely dry, but there is occasionally mist and the moisture from the mist turns the lime into a kind of cement that hardens and protects the lines. The second was that the Nazca desert experiences very little wind. The two of these conditions mean the lines have lasted for over 2000 years. There is no wind to blow gravel over them and the hard lime at the bottom of the trenches keeps them straight.
For a long time there was a lot of speculation about how the Nazca lines were made. Some people said it was aliens (of course). Some people said it was only possible to make lines that straight by being able to see them from above. It turns out that it is fairly easy to make the lines using some planning, several wooden stakes, and some rope. Archaeological excavations have discovered wooden stakes at the end of some of the lines. These were carbon dated and were of the same age as the lines.
To prove that it was possible to make the lines without alien help, Joe Nickell, an American investigator of the paranormal, produced a giant figure in a few days just using the materials that the Paracus and Nazca people would have had.
Why they were made is a far more difficult question than how they were made. There currently seem to be about five different theories.
The lines were made so that the gods they worshipped could see them. Their gods were high in the sky so the shapes had to be very large.
The lines were made for astronomy. Some of them point at specific constellations. Some of the lines point at places where the sun or other celestial bodies rise and set at different times of the year.
The lines are representations of constellations or interpretations of astronomical features.
The lines are tracks connected to irrigation channels and field divisions.
The lines are sacred paths that lead to places where deities can be worshipped and the figures represent animals and objects meant to invoke rain.
The Nazca lines could have been made for any of these reasons, or all of them, or none of them. There is no real way of knowing.
So, the Nazca lines were made using ropes and wooden stakes to mark out the design before a trench was dug. The different color of the bottom of the trench contrasted with the surrounding desert and made the lines. And this is what I learned today.
Photo By Diego Delso, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=42787825
Sources:
https://www.nationalgeographic.com/history/article/nazca-lines
https://www.history.com/topics/south-america/nazca-lines
https://www.nationalgeographic.com/history/article/nazca-lines
https://en.wikipedia.org/wiki/Nazca_Lines
https://en.wikipedia.org/wiki/Paracas_culture
https://en.wikipedia.org/wiki/Nazca_culture
https://www.joenickell.com/NazcaGeoglyphRecreator/NazcaGeoglyphRec1.html