The Inca people in Peru mastered the art of mechanically keying large granite rocks to form impressive buildings that are resistant to earthquakes like the 7.7 Richter one that struck in 1950.

There are many locations in Cusco where the original Inca constructions survive. Only mechanical keying held these huge granite stones together. |

Cusco is a major tourist attraction and the local people are friendly and helpful. |

Notice the way in which the stones are placed, with careful mechanical keying. |

There are some small protrusions on the stones which are configured to interact with sunlight. The Inca worshipped the sun. |

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Notice the sophisticated mechanical keying which made these structures earthquake resistant. |

Notice the sophisticated mechanical keying which made these structures earthquake resistant. |

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Mechanical keying held the structures together without anything cementatious between the stones. |

This is the Sun Temple. |

The steps indicate the past, present and the future. |

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Amazing workmanship. |

Chinchillas are rodents that are native to the Andes Mountains in South America. They live in colonies and are found at high elevations |

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Chinchillas |

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