A remote highland region of Vulcan, home to the masters who teach the Kolinahr discipline of pure logic, where Spock trains before Star Trek: The Motion Picture.
Gol is a desert plateau on Vulcan and the seat of the adepts who guide others through Kolinahr, the ritual by which a Vulcan sheds every remaining emotion. It is seen at the start of Star Trek: The Motion Picture.
Spock has gone there after leaving Starfleet at the end of the Enterprise's five-year mission. At the ceremony that should complete his training, a Vulcan elder touches his mind and finds that a vast consciousness calling from space has stirred his human half. She withholds the symbol of achievement, and Spock leaves to rejoin the Enterprise and seek V'Ger.
The name returns in the Next Generation two-part story Gambit, in which mercenaries hunt for pieces of the Stone of Gol, an ancient Vulcan psionic weapon that turns hostile thoughts into a killing force.