The Bingham Canyon Mine is the largest man-made excavation in the world.
This open-pit mine was opened in 1906 and still operates to this day although the current mine plan is set to expire in 2019.
The mine extracts copper, gold, silver, and molybdenum.
Here is an image of the mine in 1907.
Environmentally there have been several chemical spills between 2000-2014 among other problems - but that isn't what we're here for. To say the least there seems to be a big groundwater problem due to mining activities.