If it weren't for that really big hole in the ground, Butte reminds me of where I went to school. That too was a Copper Mining area but it was all done using deep-shaft mines, whereas Butte appeared to use a combination of open pit and shaft mining. What were you doing while in Butte?
BTW, in Hancock, Michigan, just across the river from where I went to school, there's one mine shaft, Quincy #2, that goes down over 9,000 ft, the deepest mine shaft in the world, and they could have gone deeper as the last steam hoist they installed at the mine had a take-up drum which could hold over 10,000 feet of cable. That particular mine closed when the price of copper dropped after WWII, but several others were still in operation when I started school there in 1965 but by the time I graduated in '71 they had all closed.
http://en.wikipedia.org/wiki/Quincy_Mine
Speaking of winter in the UP, here's a picture of Quincy #2 that I took in December 1971:


OCU