El Teniente Copper Mine
Codelco — Machali, Chile
Located in the Andes Mountains in Central Chile at 2,300 meters above sea level, El Teniente is the world’s largest underground mine with over 3,000 km of underground tunnels.
Operational since 1905, the 44 meter diameter stockpile dome was designed and installed in a very tight space between existing mine facilities and Andes Mountain walls.