Bigger Than US, The Berkeley Pitt, Butte Montana

The Berkeley Pit, located in Butte, Montana, is a colossal, flooded former open-pit copper mine. Once heralded as 'The Richest Hill on Earth,' it now operates as a Superfund site filled with highly acidic, heavy-metal-laden water that is managed as an environmental challenge. The pit is a mile wide and nearly 1,800 feet deep, and it has become a destination for toxic tourism, featuring a viewing stand where visitors can observe the toxic lake and its ongoing water treatment.