Ace F-135 is the first paperback appearance, 1961. It originally appeared in hardcover in 1955.
Two generations after destruction rained down upon America's cities, the population is scattered into small towns. Cities are forbidden by law, as is scientific research.
Rumors abound of a secret place known as "Bartorstown," where science is untrammelled by interference or hatred. A youth named Len Colter, developing an unhealthy thirst for knowledge exacerbated by the discovery of a forbidden radio, sets out on a long road. During this journey, he will change his mind many times before determining the correct direction for himself, and for the benighted America in which he lives.