I descended further and further into a concrete stairwell, ultimately reaching a depth of four-and-a-half flights below ground. The once expansive sky above was reduced to a narrow rectangle, and soon I found myself standing before a steel blue door.
Beyond this door, to the right, lay a long tunnel leading to a silo that had once housed a Titan II intercontinental ballistic missile equipped with a nine-megaton nuclear warhead.
I proceeded left, through another metal door and a shorter tunnel, arriving at the windowless expanse that would serve as my accommodation for the next ten nights: a decommissioned US nuclear launch control center, now repurposed into an unusual Airbnb lodging.