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In one of the most arid regions in the world a series of carefully constructed, spiralling holes form lines across the landscape. Known as puquios, their origin has been a puzzle – one that could only be solved from space.

The holes are from the Nasca region of Peru – an area famous for the Nasca lines, several enormous geometric images carved into the landscape; immaculate archaeological evidence of ceremonial burials; and the rapid decline of this once flourishing society.

What adds to the intrigue in the native ancient people of Nasca is how they were able to survive in an area where droughts can last for years at a time.

The puquios were a “sophisticated hydraulic system constructed to retrieve water from underground aquifers,” says Rosa Lasaponara of the Institute of Methodologies for Environmental Analysis, in Italy. And they transformed this inhospitable region.