Abandoned Copper Mine Tunnel: Ontonagon County, Michigan

The Adventure Mine sits at the base of the Keweenaw Peninsula in Ontonagon County. The first time it opened was in 1850 but closed down twelve years later, in 1862.

In 1863 it was purchased and re-named the Adventure Copper Company --- when 1898 rolled around, the name was slightly altered to the Adventure Consolidated Copper Company. Ten years later in 1908, production slowed down. Then World War I hit and production began again. Once the war was over, that was it for the mine…it shut down for good in 1920.

The mine sat abandoned and deserted for fifty years and then someone had the good foresight to open the mine for public tours beginning in the 1970s. The tour packages are as follows:
1) A 45-minute underground walk
2) A one hour, 20-minute underground hike
3) A three-hour tour which includes rappelling down a rope (or cable) into an 80-foot deep shaft
4) A six hour journey to the mine’s second level, including lunch

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So tours thru the old mine are great and informative…but someone seems to have found another copper mine tunnel, not far from the main mine. The opening is at the base of a hill and the tunnel goes deep straight through. The walls of the tunnel appear to be draped in some form of quartz; it’s a curious little tunnel hidden in the woods. A few photos of this tunnel are seen in the gallery below.

Surprisingly, there’s a little sign that tells the public to enter at their own risk, so evidently, they don’t try to keep trespassers away. Meantime, if you’re not claustrophobic and you don’t mind a few bats hanging overhead, the main mine tours might be the safest way to go.