Hill-Annex Mine State Park is a state park of

Minnesota Minnesota () is a state in the upper midwestern region of the United States. It is the 12th largest U.S. state in area and the 22nd most populous, with over 5.75 million residents. Minnesota is home to western prairies, now given over to ...

, United States, interpreting the

open-pit mining Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique of extracting rock or minerals from the earth from an open-air pit, sometimes known as a borrow. This form of mini ...

heritage of the

Mesabi Range The Mesabi Iron Range is a mining district in northeastern Minnesota following an elongate trend containing large deposits of iron ore. It is the largest of four major iron ranges in the region collectively known as the Iron Range of Minnesota ...

. The park is located north of the city of Calumet, in

Itasca County, Minnesota Itasca County (pronounced eye-ta-ska) is located in the State of Minnesota. As of the 2020 census, the population was 45,014. Its county seat is Grand Rapids. The county is named after Lake Itasca, which is in turn a shortened version of the La ...

. The park provides access to fossil material exposed by mining from the Cretaceous era Coleraine Formation. In 1892, the land was leased for mineral exploration. It was leased again in 1900 and mining began in 1913. In the years it was in operation, the mine produced 63 million tons of iron ore. It grew to become the sixth largest producer in Minnesota. Historic buildings include the office building (c. 1930), laboratory (c. 1930), maintenance shop (c. 1930), truck repair shop (c. 1919), wooden water tower (c. 1919), and community club (c. 1915). with After the mine closed, the Iron Range Resources and Rehabilitation Board acquired it for a dollar. They converted the community club building into a museum and visitors center and gave tours. The former mine was listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic ...

in 1986 as a historic district, and the Minnesota Legislature made Hill Annex Mine a state park two years later.

Flora and fauna

Conservationists have added vegetation to rehabilitate areas damaged by open-pit mining. The landscape is home to grouse,

deer Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the re ...

, coyotes, timber wolves, and

black bear Black bear or Blackbear may refer to: Animals * American black bear (''Ursus americanus''), a North American bear species * Asian black bear (''Ursus thibetanus''), an Asian bear species Music * Black Bear (band), a Canadian First Nations group ...

s. Raptors, including

eagle Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, j ...

s, peregrine falcons, and hawks have returned to the park.

Hill Annex Paleontology Project

The Hill Annex Paleontology Project is a research endeavor focused on the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

deposits found in Minnesota and has been active at the state park since 2014. It began as a volunteer-led study by the

Science Museum of Minnesota Science Museum of Minnesota is an American museum focused on topics in technology, natural history, physical science, and mathematics education. Founded in 1907 and located in Saint Paul, Minnesota, the 501(c)(3) nonprofit institution is staffed ...

. As of 2017, the project is now led by and housed at the

Minnesota Discovery Center The Minnesota Discovery Center, formerly known as Ironworld Discovery Center and originally as the Iron Range Interpretive Center, opened in the 1977 outside Chisholm, Minnesota, United States. It showcases northeastern Minnesota's "history and f ...

in Chisholm. This project focuses on the Coleraine Formation, a formation specifically found only in Minnesota. Many specimens previously undocumented on the

Mesabi Iron Range The Mesabi Iron Range is a mining district in northeastern Minnesota following an elongate trend containing large deposits of iron ore. It is the largest of four major iron ranges in the region collectively known as the Iron Range of Minnesota ...

and Minnesota have been uncovered over the course of this project. One of the most scientifically important finds was the end piece of a toe bone from a

dromaeosaur Dromaeosauridae () is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ('), meaning ...

in 2015, which is only the second piece of dinosaur remains found in the state. These raptors were approximately five to six feet tall and lived during the Late Cretaceous Period. Specimens found by this project also ammonites, crocodiles, and various species of fish, sharks, plant material, turtles, crabs, mollusks, snails, and clams.

References

External links

Hill-Annex Mine State Park

Hill Annex Mine Paleontology Project

Hill Annex Mine Fossil Gallery
1988 establishments in Minnesota Industrial buildings and structures on the National Register of Historic Places in Minnesota Mining museums in Minnesota Protected areas established in 1988 Protected areas of Itasca County, Minnesota State parks of Minnesota Museums in Itasca County, Minnesota Mines in Minnesota National Register of Historic Places in Itasca County, Minnesota Surface mines in the United States Iron mines in the United States {{Minnesota-NRHP-stub