I had to search that
Supposedly Satanic numbers adorn this preserved submarine sail.
www.atlasobscura.com
After being decommissioned in 2000, the monument was placed in the roadside Idaho Science Center to honor Arco's long association with the Navy and the nuclear fleet in particular.
Specifically, for just 60 minutes on July 17, 1955, Arco was the first city on Earth to be lit solely by nuclear electricity, thanks to the BORAX-III reactor at the Idaho National Laboratory (then called the National Reactor Testing Station).
A more morbid record was that it was the first fatal nuclear accident, and so far the only one in the U.S.