After centuries of rumor and speculation, archaeologists have finally confirmed the existence of a colossal underground tunnel system beneath the Peruvian city of Cusco. Built by the ancient Inca, the labyrinth – or Chincana – radiates outwards from the Temple of the Sun, extending for more than a mile towards a fortress on the edge of the city.The discovery was announced at a press conference during which researchers explained how they located the subterranean passages in three stages. The first of these involved studying historical texts from the 16th to 18th centuries in search of references to the Chincana and...