Arco, Idaho

A small town in south eastern Idaho considered the "first city in the world to be lit by atomic power," which was provided (at least for an hour), by the nearby National Reactor Testing Station, on July 17, 1955. That reactor is now part of the nuclear complex at the Idaho National Engineering Lab. (Moorpark, California also makes this claim, from a reactor at the Santa Suzanna Field Lab, but that occurred in November, 1957).