About Berkeley Pit
From the viewing stand on Butte’s east side, the Berkeley Pit looks like a lake set inside a terraced crater. It was an open-pit copper mine until operations stopped in 1982. As pumps shut down, groundwater began filling the excavation, turning an industrial landscape into an unnerving expanse of water.
The lake is highly acidic and carries dissolved metals, so its still surface should not be mistaken for a recreational lake. The surrounding mines and town tell the larger story of Butte’s copper boom, its immense engineering, and the lasting work of managing its environmental legacy. Interpretive signs at the stand give visitors a sense of scale without taking them near the water.
The viewing platform is usually a seasonal stop, and an admission fee applies. Check the operator’s current hours and price before going. The dramatic panorama is the appeal: a century of mining history visible in a single, almost impossible-looking hole.