Soudan Underground Mine State Park 
The Soudan Mine on the Vermilion Range is the oldest and deepest iron mine in Minnesota. Its opening in 1884 set the stage for Minnesota’s reign as the country’s leading iron ore producer. In the late 1800s, prospectors searching for gold in northern Minnesota Had discovered extremely rich veins of hematite at this site, often containing more than 65% iron. 
From 1901 until the end of active mining in 1962, the Soudan Mine was owned by the United States Steel Corporation's Oliver Iron Mining Division. By 1912 the mine was at a depth of 1,250 feet (381 m). When it closed, level 27 was being developed at 2,341 feet (713.5 m) below the surface. US Steel then donated the Soudan Mine to the State of Minnesota to use for educational purposes.

After shipping ore every year but one, the Soudan fell victim to technological advances and a changing economy. By the time it closed in 1962, the mine had reached a depth of almost 2,500 feet, with tunnels that ran nearly a mile to the east and west. Today the Soudan Mine is the country’s only underground iron ore mine open to the public as a state park. Unlike most underground mines, the Soudan, with its solid rock walls, has no supporting timbers in its mineshafts. Near the mine entrance the engine house (1901), crusher house (1904), drill shop (1917) and dry house (1925) still stand

The State Park is in Breitung Township, on the shore of Lake Vermilion in northern Minnesota's Vermilion Range. The mine is close to Minnesota State Highway 169, about 20 miles east of Virginia and 20 miles (30 km) west of Ely, about one mile from Tower. It is a popular tourist site, often visited on the way to and from Ely and the Boundary Waters Canoe Area Wilderness.
Operated under the Department of Natural Resources, it is a National Historic Landmark. The surface buildings are open to the public, and during the summer months there are daily tours of the mine. Visitors are lowered in an 80-year-old electric mine hoist to level 27, the mine's lowest level at 2,341 feet (713.5 m) below ground. Two tours are open to the public: one that explores the historic mining facilities, and another that focuses on the currently active underground physics laboratory.
Number 8 Shaft - 1900
Open Pit Operation 1890
In 1880, Charlemagne Tower, a wealthy Pennsylvania industrialist, purchased some 20,000 acres of iron-rich land in northern Minnesota for development. Within two years he had incorporated the Minnesota Iron Company and gained control of the Duluth & Iron Range Railroad to ship ore to his docks in Two Harbors. More than 100 experienced miners were brought in from Michigan to work the Soudan Mine site. Originally seven open pits in 1882, the mine suffered frequent accidents from falling rocks, forcing operations underground in the 1890s.
Mine Tour: From Memorial Weekend to Labor Day tours run every hour from 10:00 am to 4:00 pm, Monday to Sunday. After Labor Day through the end of September, tours are offered daily at 10:00 am, 12:00 pm, 2:00 pm, and 4:00 pm (on the hour from 10 to 4 on weekends). Tours are offered on weekends in October through October 21st hourly from 10 a.m. to 4:00 p.m.

Physics Tour: From Memorial Weekend to Labor Day tours run at 10:00 am and 4:00 pm. After Labor Day through the end of September, tours run daily at 12:00 pm. From October through October 21st tours will be offered on weekends at noon.

Admission: (per person): Adults (13 and older): $10; children 5-12: $6; children 5 and under: no charge. A state vehicle permit is NOT required.