We had heard about the The Berkeley Pit in Butte and since we were there wanted to see it. At one time it was America's Largest Truck-Operated Open Pit Copper Mine. Now it's a 500-acre lake of deadly drainage, 1,800 feet deep and a mile across. The pit holds over 40 billion gallons of waste so deadly that in 1995 it killed over 300 snow geese that mistakenly landed on it. The snow geese slaughter happened again in late November 2016, when 10,000 of them landed on the liquid and thousands succumbed to the pit's deadly waste water.
Unfortunately, it was closed. There is actually a tunnel that you walk through to access the viewing platform. It is looked after by the Chamber of Commerce. The hours on the sign said it was to be open but it wasn't and calling the Chamber's phone # only led to voice mail.
We did walk up the hill on a well beaten path beside the visitor center but they have a fence and a mound of dirt all away around the lake so we didn't see much.But maybe another time. There seems to be alot of history to this old place.