Hill Annex Mine State Park
This park on the Minnesota Iron Range is a 500-foot-deep hole in the ground. The Hill Annex Mine, listed on the National Register of Historic Places, was one of the nation’s largest open-pit mines, generating over 64 million tons of iron ore during its 66-year existence.
Hill Annex Mine State Park is located in Calumet in Minnesota’s Itasca County.

Nature is slowly reclaiming a landscape scarred by open pit mining
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Visitors can experience the immensity of the mine by taking a 90-minute trolley bus tour, which travels over 300 feet down into the pit. Another popular attraction is the fossil hunt tour, where visitors can discover remnants from the Cretaceous period and take home what they find.

Ore samples were processed in the laboratory

Some of the old machinery is on display here

A typical room in a mine worker boarding house
Mining equipment, former mine worker boarding houses and ore processing buildings are part of the display at this park. Hill Annex Mine is one of the access points for the 130-mile paved Mesabi Trail. No campsites are available here.

After the ground water pumps were turned off in 1978, the former mine pit slowly filled with water.