How to ID a Shaft

Its that time of year again when people – suffering from great bouts of cabin fever – venture out into the Keweenaw backwoods in search of old mine ruins to explore. With the leaves not yet on the trees and the snow melting – these ruins are easier to find and photograph then ever. Its a great time to go exploring, and also a great time for me to do a little public service announcement on the dangers of mine shafts.

When talking about mine safety its always good to remember the story of 7-year old Ruth Ann Miller. While playing around the Tamarack No. 4 shaft, she somehow managed to slip under the cap and fall down the shaft. During rescue attempts the cap broke in two and fell down the shaft as well – sealing Ruth over 400 feet under the ground. While kids like Ruth are at greater danger of falling down an abandoned mine shaft – anyone can fall victim if they’re not careful.

The most important thing to remember when exploring old mine sites is to always pay attention to your surroundings. In most cases mine shafts can be detected long before you get close enough for them to pose a danger. Knowing how a mine shaft typically presents itself in the wild and identifying the signs that accompany it is an important first step in keeping safe at a mine ruin. Towards that end I decided to make of list of what to look for when avoiding a potential fall down a deep mine shaft.

Danger Signs

This one may seem obvious, but in a great deal of cases a mine shaft is in fact marked by a “danger sign”. However, on most of these cases the writing on these signs have been worn – or shot – off. What you will find is a blank piece of metal attached to a metal pole, tree, or wood post. If you find one in the middle of the woods – it marks a mine shaft.

Barbed Wire

Every single mine shaft I have discovered has been marked with barbed wire. In some cases this wire is still attached to a standing fence, but in most cases it is not. But while fences and wood posts will rot away over time – the rusted steel of the barbed wire will always remain. Often it’s laying about on the ground, or hanging up against a tree. In some old mines I have seen the wire imbedded into nearby trees. If you see barbed wire on the ground – a mine shaft is close by.


This is more rare then it should be – but you will find times when an actually fence is sealing off a shaft opening. Often, however, these fences are in poor shape and falling down. Above you can see the fence around an Osceola Shaft (with a sign as well). These fences can be in the form of a snow fence, wood posts, or even chain-link in some cases. Either way – obey their warning and stay away.


While the sample I show here is extreme, most shafts can be identified by a depression in the ground. These depressions can vary in depth – from the extreme as seen here, to more subtle as seen most other places. These depressions often seem “out of place” to the area around it – without any trees or plants growing within them. Often their steep sides are lines with poor rock, or some other “out of place” material. In general its always a good idea to not go near depressions – even ones that you think are probably not a shaft.


Often you will stumble across a line of metal pipes in the woods, like seen in the examples above. In a lot of cases these pipes are not attached to any time of fence, they simply stand alone in the woods. Sometimes they have back braces to help hold them up, sometimes they are laying down on the ground or are broke in two. No matter how you find them, these pipes always mean a shaft is nearby. Stay away from them.


If a shaft has been capped correctly, it often is marked by a vent pipe like what’s seen here. Sometimes the vent is large, or sometimes its just a large steep pipe sticking up out of the ground. While this often means the shaft has been capped correctly, you should still avoid them. Just to be safe.

Concrete Pads

Another sign of a more recently capped shaft is the concrete pad. These are often rectangular in shape, sitting seemingly by themselves in the middle of the woods. They are usually only a few inches in height, covered in a good layer of moss. While you might think this is just a foundation to another building, there are a few ways you can tell the difference. First there are very few concrete slabs used in mine construction – except for the case of a collar house. (which would also contain the shaft so it should be avoided). When concrete “floors” are used they are most often etched into a tile pattern. They will also be edged by a slight concrete “lip” standing a few feet above the pad. In most cases they will also feature other “do-dads” across its surface. If its a flat, featureless concrete slab it most likely is a cap.

I hope this comes in handy to some of you fellow explorers (and wanna-be explorers) out there. So go out there and have some fun exploring the Copper Country – just stay away from mine shafts and stay safe!

Show More


  1. The Pasty Cam posted pictures of the Tamarack #4 shaft cap and the memorial to the girl who lost her life there. July 16, 2006 was the 40th anniversary of the tragedy – CLICK HERE

  2. A couple additions — look for a sudden but small mound of poor rock or earth. Frequently that’s been piled over an old shaft to “keep ‘er shut for good”, or just piled over a real cap (such as the Firefighter’s memorial in Calumet).

    Another thing to be careful about — many of the older shafts are now hidden in small groves of trees or bushes, even in otherwise clear areas. This is partly because anybody clearing the area near them for lumber, building, etc. doesn’t want to drive a heavy vehicle across a cap, so it gets overgrown. Some of those trees may be planted deliberately to keep people out. Some of the shafts at Ojibway and Copper Falls are good examples of this.

  3. dcclark –

    The grove of tree’s is a good one that I forgot. I’ve seen this a lot near Calumet and along the gap. The best example of that is N. Kearsarge No. 1 – a small tightly knit collection of brush and trees sitting in the middle of a field. It was a rather bit too obvious – but that’s a good thing in this case. So don’t go fighting your way into overgrown areas – not a good idea.

  4. Thanks for the heads up. Most of the shafts I’ve come across to date belonged to either CRI or C&H and thus are typically well-capped, rather obvious, and easy to avoid. When you start heading out to other sites though (Central comes to mind as an example that I’ve visited), sometimes they were abandoned rather hastily or they were left behind too long ago to have benefitted from more modern capping techniques. So it’s good to have a working knowledge of suspicious things to watch out for, besides conspicuous items like warning signs and concrete caps.

  5. I just ran across a govt. website for kids explaining the dangers of abandoned mines and thought about forwarding a link. I ran across it while Googling “danger mine” in search of a sign like the one in the first picture.

    If I’m not mistaken, another thing to watch for during winter exploring is steam coming from out of the ground.

    Here’s a shot of a capped mine shaft at the Tamarack location. It’s got almost all the examples of a capped shaft: fence (not pictured), old cars, poor rock and a vent. The thing that blew me away was that this was just around the corner from the Ruth Ann Miller memorial at the #4 shaft.

  6. I’ve tried to use the “watching for steam” trick before, but it’s very difficult — only on the right kind of winter day (proper temperature and humidity), and usually only with wide open shafts. For example, the old #5 at Quincy (with a huge bat cage over it) shows up well, but mostly covered shafts don’t.

  7. Jay – I’ve seen that one before, the first time I went looking for the Miller shrine; it’s literally right down the road. Very dangerous – to unsuspecting children, it might just look like an interesting pile of rocks.

  8. Tim,

    When we were there in August there was a pretty tall fence around the entire area. I can’t believe that there wasn’t an outcry to put a better cap on it from the locals right after the Miller tragedy.

    We ran across it right after visiting the shrine at the #4. While driving around I noticed the fence and said “Hey, another shaft.”

  9. Been x-country skiing the Norwich
    Bluff area for many years. Lots of
    open shafts which are hidden by 4 feet of snow during winter. It scared
    the heck out of me when I saw what I
    skied near in the summer.

Leave a Reply

Your email address will not be published. Required fields are marked *