Lost Cities of the Ancients - Season 1 Episode 2 -

In the Lambeyeque valley in Northern Peru lies a strange lost world – the forgotten ruins of 250 mysterious pyramids, including some of the biggest on the planet, colossal structures made out of mud bricks. Long ago, the Lambeyeque people were haunted by a terrible fear and believed that building pyramids was essential to their survival. Their obsession reached its height at a city called Tucume, an eerie place of 26 pyramids standing side-by-side, the last pyramids this civilization created before they vanished forever.