Located right across the road from the dredge are the remains of Quincy Stamp Mill No. 1. This was used by the Quincy Mining Company for the liberation of native copper from ore that came out of their nearby mines. From what I can gather the structures that are still standing were built around 1920 while older parts of the complex were constructed between 1888 and 1922. Quincy Stamp Mill No. 2 was demolished sometime after World War Two and what's left of it can be found about 800 feet NE.
The largest section of this area is undoubtedly what you see from the road. The first level is mostly full of wood and old debris. There are a few concrete staircases that haven't crumbled yet that you can take up the second level. After you reach the second level and are out from under the roof, there's a trail that leads north to a small valley that will take you to a second two story turbine house. There's a cobbled together ladder that you can get to the second story with. The second story is an awesome place to make a bonfire too due to its enormously high ceiling, windows and graffiti.
There's also a large tunnel that runs under the valley that you can get to by taking a left on the trail at the base of the valley. Lastly there are some tunnels around the old ruins to the north. Those are just okay though. Overall this is a must see and since you've gotta park here to see the dredge, you might as well check it out!
To get here, head north on the lift bridge and turn left onto M-26. Drive for about 6 miles. You'll pass through a town called Mason. If you get to Hubbell you've gone too far. At 6 miles you'll see the dredge on the water to your right and the abandoned Quincy Mill to your left. Park in the dirt lot in front of the mill.
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