The Stanley R. Mickelsen Safeguard Complex in Cavalier County, North Dakota, is the focus of an amazing set of images hosted by the U.S. Library of Congress, showing this squat and evocative megastructure in various states of construction and completion.
It's a huge pyramid in the middle of nowhere tracking the end of the world on radar, an abstract geometric shape beneath the sky without a human being in sight, or it could even be the opening scene of an apocalyptic science fiction film—but it's just the U.S. military going about its business, building vast and other-worldly architectural structures that the civilian world only rarely sees.
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One structure was built as part of a kind of analogue system for tracking divine events and celestial calendars, as dark constellations of gods spun across the sky; the other was a temple to mathematics built for guiding and pinging missiles as they streaked horizon to horizon, a site of early warning against the apocalypse, as a new zodiac of nuclear warheads would burst open to shine their world-blinding light on the obliterated landscapes below.