For a CONUS campaign, I just learned about a series of bunkers constructed in the 1960s to protect the AT&T L-Carrier Cable Network, securing coast-to-coast telephone and TV comms.
https://www.thedrive.com/the-war-zon...i-can-be-yours
https://www.saltriverproperties.com/...65275/1047712/
If you've got the dough and are looking to relocating to the Midwest, you can buy this 8,300 square foot underground bunker for a mere $430,000 (some reno required).
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