Wrong-Way Street
First published in Galaxy, April 1965. Astronaut Mike Capoferri, haunted by a childhood accident, discovers a time-travel device left behind in an abandoned alien base unearthed on the moon. Can he master the device and change the past, or is time truly a one-way street?
A stand-alone time-travel story. Niven credits his editor, Fred Pohl, with a great deal of help with this story: "He published my second story, "Wrong Way Street," in Galaxy. The title is his. He felt it needed a new first chapter for coherency, and he wrote that too."
Note that the story reappears in Convergent Series without the hyphen in the title.
Anthology, The Ninth Galaxy Reader, edited by Frederik Pohl, 1966; anthology, Voyagers in Time, edited by Robert Silverberg, cloth and paper; anthology, First Flights to the Moon, edited by Hal Clement, cloth; Portugese anthology, Viajantes No Tiempo, as "Rua de Sentido Unico," from Galleria Panorama; anthology, Twelve Great Science Fiction Stories, ed. Robert Silverberg. Grosset & Dunlap, 1970, paper; anthology, Die Morder Mohammeds, as "Falsche Richtung," Marion von Schroder Verlag, 1970; as "Tweerichtingsverkeer," in Alfo Een copyright 1973 Muelenhoff Nederland bv; Convergent Series