A picture of the ore docks in Duluth Minnesota. The picture is somewhat old (few months) but it gives a sense of scale. I believe that the docks fit 2 ore haulers, they are the biggest things in the port by far. The next closest is the coal docks on the other side of the port.
I unfortunately don't have a picture of the ore (tactonite ~50% iron). I'll try to grab one when drive by on Monday or there abouts. It may not be as full as other areas due to the flooding up here knocking out some rail lines.
*correction
The ore docks on the Wisconsin side are of a similar size.
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