Also see Chucicamata One of these two copper mines in the north of Chile is the largest man made hole, the other is the largest open pit mining operation. La Escondida has a convenient location on the Salta (Argentina) to Antofagasta (Chile) Railway Line. The famous Tren a las Nubes (Train To the Clouds) runs on the Argentinian side.
Watch the company's nice flash animation that shows the copper production process: |