THE CARDONA SALT MOUNTAIN AND TUNNEL

 

The Cardona Salt Mountain in Spain is a huge geologic formation made almost entirely of the world's favorite edible mineral.

 

Formed two million years ago when low-density salt was pushed up through the much harder materials surrounding it, the Cardona Salt Mountain is one of the largest domes of its kind in the world, and unique in Europe.

 

While small amounts of other minerals pervade the savory hill, the salt pile would have a near translucent quality if not for the thin layer of reddish clay coating the exterior.

 

The significance of the mountain was recognized as early as the middle ages when Romans began exploiting the mountain for its salt, which began to bolster the young Cardonian economy.

 

With the invention of industrial mining techniques, a mine was built into the side of the mountain and a thriving facility formed at its base as excavators dragged enormous amounts of potash (water-soluble) salt from the innards of the hill. 

 

In addition to the mineral export, the locals of Cardona began making salt sculptures to sell and invented a number of hard, salty pastries unique to the area.

 

Read more and see picture gallery of this amazing cave -  http://www.atlasobscura.com/places/cardona-salt-mountain

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