A half-mile below the surface at the Soudan Underground Mine State Park, home to Minnesota's oldest iron ore mine, visitors get to take a 3/4 mile train ride to the last and deepest area mined-level 27, which was being developed at 2,341 feet below the surface. Over the life of the mine, 54 miles of tunnels were dug 2,350 feet deep, and more than 15.5 million tons of ore were mined. The Soudan Mine was owned by the United States Steel Corporation's Oliver Iron Mining division and in 1965, US Steel donated the Soudan Mine to the State of Minnesota to use for educational purposes.
The mine was started in 1882 and went underground in 1892 and closed in 1962 and stopped shipping ore from the stockpile below this trestle in 1963. For more info: http://www.dnr.state.mn.us/state_parks/soudan_underground_mine/index.html
