Different doors for different vehicles, I would guess. White Pine Mine used tire-based vehicles, rather than track-based, making it pretty different than other mines I’ve been to.
A guard shack on top of a hill in the middle of the base. The hill separates the launch pad from the warhead storage building. In other configurations the launch pad is down the road from the Integrated Fire Control buildings, but at MS-40 it was all on one site.
Before developers saw to cut and cut the flour mills inside Pillsbury, they stood at the ready beside various purposeful chutes the traversed the floors of between sorters. These machines were belt-driven by the power of Pillsbury’s Mississippi headraces and turbines, the force of which notoriously shook the building’s foundations themselves. The wheels would change the grade of the flour, or the size of the dust produced from crushing the kernels.
The main gate, as seen in 2005. It hasn’t changed much since then.
The Engine House’s boiler, which would have been fired all day all day, virtually from the day the shop opened until the day it closed.
Near the guard post protecting the launch pad at the Duluth BOMARC is an orange windsock.
A cracked sign at dock-level, where loading boats would be tied below the taconite conveyors. All across the surface of the concrete dock were taconite pellets, like slippery little marbles. One wrong step could put a worker in the water, which is a bad, bad place to be.
This building stood on stilts until it was demolished. The top floor handled radio traffic to boats and trains. The bottom floor had locker rooms, records, and a lunchroom.
Looking past the Osborn along the side of the Hughitt Slip, where there have always been grain elevators for more than 100 years.