Soudan Underground Mine

The Cadillac of Mines

Soudan, Highway 1 between Ely and Virginia, Mesabi Iron Range, Northern Minnesota

Site: http://www.dnr.state.mn.us/state_parks/soudan_underground_mine/index.html. Please always confirm the below rate and times information with the official site!
Tour Prices: Each 1.5hr tour costs $10.00 for adults ages 13 and older, $6.00 for youth ages 5 to 12. There is no charge for children under age 5.
Accessibility: Please call the park office at 218-753-2245 for more information regarding the accessibility of the tours. Parts of the tour will most certainly not be accessible.
Hours of Operation: May to September: Daily, 9:30 a.m. - 5:30 p.m.

Facts:

• The country's only underground mine open to the public (according to National Register of Historic Places).
• Oldest and deepest in Minnesota (source, ditto).
• There are no supporting timbers - the mine is solid rock throughout. (source, tour guide)
• Regardless of outside temperature, it's cold down there. Bring a coat.
• Part of the mine currently houses Fermi National Accelerator Laboratory’s (Fermilab) Main Injector Neutrino Oscillation Search's (MINOS) particle detector. Tours run separately from the "iron mine" portion tours.

We were heading up to Bear Head Lake for some mid-autumn camping. Instead of taking the usual Highway 61 along the North Shore, we decided to take the alternate route, going straight north out of Duluth, inland and across towards the park. This route was more featureless, with the green monotony being broken up by the reds and yellows of autumn. However, even with no lake to dictate the road's path, the ample hills of the Iron Range meant a lot of winding.

Upon exiting the town of Soudan, mere miles from our destination, a particular twist in the road revealed what looked like an old mine elevator shaft tower. A sign up ahead informed us that the Soudan Underground Mine was in fact open for visitors still. As we have only been to the ornamental Wieliczka Salt Mine and were curious to see how a functional taconite mine would compare, we made plans to go the next day.

The parking lot can accommodate perhaps 50 cars; there were 4 there when we arrived. The above ground structures are all open to visitors, an unusual site in safety-paranoid America. The rust and ore dust are ever present, and the heavy machinery looms silently in the grinder and crusher rooms. It's easy to be deafened by this silence, simply gazing into the huge, crude metal teeth and imagining the atrocious noise levels this brute force process created. The ore carts above the grinder and crusher are almost cute on their elaborate electrical tracks running 20 feet from elevator to the crusher room - the simplistic setup briefly reminds me of working cable cars at an amusement park, using manual force to stop and release the carts. What we use for amusement now was back-breaking labor not so long ago - figures. The final testament to the mine's defunct status can be found by walking out onto the delivery platform; the rail below it extends two hundred feet in either direction and ends in brush. There is no longer any sign beyond that an active railroad line ran through here.

We wander slowly back towards the elevator tower and the engine building. It contains the parts from the previous winch mechanism, the current one consisting solely of a huge cable drum, an on/off switch and a half-asleep operator. Of course the schedule is much less onerous with no actual ore coming up, and tours running only on the hour and half hour.

Our guide is a semi-retired mine worker; I guess you could say he still works the mine. His voice is somber yet engaging, and knowing that it's all personal experience lends the entire tour an air of quiet respect. He fills us in on the basic history as we wait for the "all clear" signal from the bottom of the elevator shaft.

The Soudan mine was opened in 1882 as an open pit mine, and quickly grew profitable due to the high oxygen content in the ore. As the miners dug deeper (our guide explained) the poor-to-nonexistent safety regulations failed to prevent the sides of the pit from falling inward, and operations moved fully underground by 1900. Eventually, advances in technology made artificial oxygen injection possible and cheap, and the costs of mining Soudan outweighed the benefits of the valuable ore. The mine closed in 1962 having reached level 27 below ground at a depth of 2,341 feet (713.5 m).

Throughout its history the mine was known as a good place to work. For one thing, its starting out as a pit meant that there was ample ventilation - some quirk in its layout also meant that a soft wind is, somehow, constantly reaching a substantial part of the shafts. Another quirk of its structure, possibly enhanced through clever digging, meant that it was dry, the runoff collecting in predictable and easily avoidable places. Not working in mud and having fresh air were huge and unusual luxuries in these early mines - hence the "Cadillac of Mines" designation.

The shaft and the cages are more or less original, and it shows. The descent is rather loud, shaky, and windy. As we crowd inside the small elevator cage, our personal space bubbles compressed to almost nothing, our guide off-handedly remarks that the cages typically carried four times as many miners per trip. It's only one of the moments we're stunned into silence, despite knowing this before - the reality of it all around us.

The bottom of the mine is cool and well-lit; it feels like the basement of a large, well air-conditioned university building rather than half a mile underground. We begin to understand what a difference that would make in a full shift full of hard labor.

Unfortunately there isn't much to be seen; as a functional mine, Soudan isn't very visually appealing underground. Once you travel a quarter of a mile on a small electric train in near-complete darkness, travel up a few flights into the last emptied cave that's about it. However, the presentation in that last, unfinished iron vein is worth it alone. The guide goes through the history, the techniques used and the evolution of light technology throughout the mine's existence and the impact of the demonstration is severely magnified by actually being there.

Emerging into daylight was just as you'd expect it. Sunlight is a very startling thing even after spending merely an hour in the darkness, as is wind. If you've never been spelunking or haven't had a chance to visit a mine, I highly recommend it.

Allow me to close on quick note about mining technology. The veins (or is it lodes?) of ore run horizontally through the bedrock. The way these were mined in Soudan was this:

1. Locate your lode.
2. Dig/blast vertical shafts through it to the rock below.
3. Dig a horizontal shaft (a gallery) below the lode with cart access.
4. Start loosening/blasting ore on the top level and throw it down the shafts dug in step 2; this ensures the cleared ore is gone from the work area.
5. Continue digging downward until you hit rock.

After reading up on mining methods this seems to be called room and pillar - except modified, using shafts to clear the working floor by dumping the loosened ore/rock rather than simply carting it out. After clearing out all the ore you end up with a very large open room - this is only possible because, again, the rock surrounding the ore is very stable.

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