Tucked high in the Andes Mountains of northern Peru is a remarkable fossil locality: a 39-million-year-old petrified forest preserved in nearly pristine condition: stumps, full trees, leaves and all. With its existence unknown to scientists until the early 1990s — and its significance unbeknownst to villagers — this ancient forest hosts the remains of more than 40 types of trees, some still rooted, that flourished in a lowland tropical forest until they were suddenly buried by a volcanic eruption during the Eocene.