"The Road Not Taken" is a science fiction short story by American writer Harry Turtledove, in which he presents a fictitious account of a first encounter between humanity and an alien race, the Roxolani.

When they are interrogated, the truth becomes evident: the method of manipulating gravity is absurdly simple, and species that discover it are able to use faster-than-light travel with primitive technological sophistication.

As Togram and another Roxolani captive realize that they have now given a far more advanced civilization the means to travel to countless worlds, the story closes with the two asking themselves, "What have we done?"

[1] It is a prequel story to "Herbig-Haro"—set several centuries after humanity has conquered the Orion Arm of the Milky Way— published a year before under the name "Eric Iverson".

This short story contains ideas which were later more developed in the Worldwar series, in which the invading aliens have an initial technological edge that is soon surpassed by human ingenuity and innovation.