THE SALT MINES OF THE ANDES.

The salt mines, known as Salinas de Maras, in the Sacred Valley, are at 3,200 meters above sea level, near the small town of Maras.
The salt mines traditionally have been available, without putting a price over it, to any inhabitant of the Andes wishing to harvest salt. The owners must be members of the community that act as guardians of the mines. The size of the salt pond assigned to a family depends on the family's size. There are many unused salt pools available to be farmed. Any prospective salt farmer need only to locate an empty and unmaintained pond, learn how to keep a pond properly within the accepted communal law, and start working as a farmer.
The mines have been a source of salt for the Andean people since very ancient times. The exposure of the extremely salty water at the surface level to the heat of the sun at that altitude level, causes the water to evaporate, leaving the crystal salt behind.
The highly salty water obtained in Maras comes from a local subterranean stream. The flow of the stream runs into a complicated system of tiny canals that are naturally channelled inside the earth after its bubbling composition of salt and water emerges to the surface at a spring that is a natural outlet of the underground stream, situated on a hill above the salt mines.
The flow then is directed into an intricate system of tiny channels constructed in a way that the water runs gradually down onto the several hundred ancient terraced ponds.
The extremely salty water now irrigates a huge number (6,000) of small and shallow salty pools strategically dug into the mountainside. All the pools are necessarily shaped into polygons with the flow of water carefully controlled and monitored by the pond's keeper. The altitude of the ponds slowly decreases, so that the water is able to flow in a controlled way through the myriad branches of water-supply canals and be introduced slowly through a notch in one side-wall of each pond.
The proper maintenance of the adjacent feeder channel, the side walls and the water-entry notch, the pond's bottom surface, the quantity of water, and the removal of accumulated salt deposits requires close cooperation among the community of users and the pond's keepers.
The salt is mined through the evaporation of the brine (mixture of salt and water) channeled into the pans, a process that has been practiced for centuries by the Andean people.
Though the salt pans themselves are man-made, the extremely salty water comes from a subterranean natural water spring which is mixed with salt deposits from prehistoric salt lakes. Over millions of years, tectonic plate movement has buried the deposits deep beneath the mountains: the salt has found its way out from the underground level by mixing itself with the natural spring of water resulting in a flow of brine (a mixture of salt and water).
As water evaporates from the sun-warmed pools, the water becomes supersaturated and salt precipitates as various size crystals onto the inner surfaces of the pond's earthen walls and on the pond's earthen floor. The pond's keeper then closes the water-feeder notch and allows the pond to go dry. Within a few days the keeper carefully scrapes the dry salt crystals from the sides and bottom of the earthen pool and place the dry crystals into a suitable vessel. When all the crystals are removed, the keeper reopens the water-supply notch, the pan is filled again with the mixture of salt and water (brine). Then the pond's keeper carries away the salt crystals. The color of the salt crystals varies from white to a light reddish or brownish tan, depending on the skill of the individual worker.
Today, 6,000 salt pans exist near Maras, and each one is no more than 13 square feet and less than 1 foot deep. Each pan is owned and mined by a local family of the Maras community, and the salt is collected and traded in local market places or nearby towns.
It is believed that the salt pans were originally designed and constructed by a civilization that predated the Inca time. However, the Inca saw the opportunity of harvesting the salt of Maras and expanded the salt pans further up the mountainside. The way of the mining process was designed by the Incas and the whole community still agreed that the cooperative system has to be maintained in the exact way that the Incas did.
The salt mines offer overwhelming view when seeing from above access road. The large amounts of salt deposits are in the middle of the Andes Mountains, known as the heart of the Andes..