round 1545, so the story goes, a herder named Diego Huallpa climbed a mountain in the altiplano, an Andean plateau stretching across what is now western Bolivia, in search of a missing llama, only to stumble upon a seam of silver. The recently overthrown Inca empire considered this peak to be sacred, but the Spanish conquistadors, who had heard about the discovery, swiftly started mining. The mountain, which became known as Cerro Rico (Rich Hill),
