Wazee Lake

From http://www.co.jackson.wi.us/html/forestry/scuba.htm:
The lake was the site of the former Jackson County Iron Mine quarry. The mine was in operation from the early sixties until April of 1983. Approximately 850,00 tons of iron-rich taconite pellets were produced at the mine each year, with the bulk of them used for steel production in mills located in East Chicago, Indiana. A crash of the domestic steel markets in the United States contributed to the decision to close the mine... Today, Wazee Lake is recognized as the deepest inland lake in the State of Wisconsin with a maximum depth of 355 feet...Although all machinery was removed from the quarry upon its closure, remnants of the mining operation still remain visible underwater. A series of circular haul roads wind around the pit, where divers often find artifacts including chains, pipes; taconite pellets, and iron shovel teeth. Massive boulders and shear cliff faces create challenging and interesting features for the more experienced recreational diver.