Gol was an ancient city on the planet Vulcan.
In a Vulcan telling, Gol was destroyed after a soldier named Nirak mistook the approach of an invading army for a sandstorm, and failed to sound the alarm. Henceforth, "Nirak" became the Vulcan word for "fool". (ENT: "Kir'Shara")
Ronald D. Moore stated that Gol was also name of the plateau where Spock studied in Star Trek: The Motion Picture. (Star Trek: The Next Generation Companion (2nd ed., p. 267)) This correlation is also made in Gene Roddenberry's non-canonical novelization of Star Trek: The Motion Picture.