Sajama Lines

The Sajama Lines of western Bolivia are a network of thousands (possibly tens of thousands) of nearly perfectly straight paths etched into the ground continuously for more than 3,000 years by the indigenous people living near the volcano Sajama. They form a web-like network that blankets the Altiplano.

Recent research revealed that this network of lines covers an area of 22,525 square kilometers, approximately fifteen times larger than the area covered by the Nazca Lines in Peru. Rough estimates put their linear length at approximately 16,000 kilometers, roughly three times the breadth of the United States. As such, the Sajama Lines are the largest archaeological site in the Andes and might be considered the largest artwork in the world.

The lines were created by scraping aside vegetation and the dark surface material consisting of soil and oxidized rock and exposing the lighter subsurface material. Like the better-known Nazca Lines (which differ from the Sajama Lines in that some of the Nazca are depictions of animals) neither the purpose of these lines, nor how the makers achieved such precision, are completely understood.

Scholars at the University of Pennsylvania describe:

While many of these sacred lines extend as far as ten or twenty kilometers (and perhaps further), they all seem to maintain a remarkable straightness despite rugged topography and natural obstacles. The sheer number and length of these lines is often difficult to perceive from ground level, but from the air or hilltop vantage points, they are stunning.

Many believe that the lines were originally used by indigenous people when they made sacred pilgrimages. Interspersed among this network of radial lines and aligned to where lines meet are wak'as (shrines), chullpas (burial towers) and hamlets, making the area a unique cultural landscape. Though the region is now sparsely populated there is evidence that some of the lines are still in use as footpaths.

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Wikipedia