In ancient times, Gol was a city on the planet Vulcan. It was destroyed in a great conflict during the Time of Awakening. In the modern era, the city has lent its name to the mountain ranges and vast plains of the region. (ENT: "Kir'Shara"; TOS novels Sarek, Spock's World)
The archaic language known as Ancient Golic Vulcan originated on the Plains of Gol during the earliest times of Vulcan history, and by the modern era, had given rise to the formal dialect of Old High Vulcan. (TOS novel The Lost Years)
The study of kolinahr was centered on the plateau of Gol. Many temples were built in the nearby Mountains of Gol, most notably on and around Mount Seleya to the southeast. (TOS novel The Lost Years; LUG The Way of Kolinahr: The Vulcans)
The fabled Stone of Gol was constructed in the Gol region before the Time of Awakening. (TNG: "Gambit, Part II")
In 2379, the Sinclair twins visited the Gol region while studying on Vulcan. Their friend Samok frequently made trips across the plains. (Star Trek: Pendragon: "True North", "The Forgeman")