For additional meanings of "Gateway", please see Gateway.
Gateway was a site on the planet Vulcan which led into the Forge. It was believed to be the area where Surak began his pilgrimage into the Forge.
Jonathan Archer and T'Pol traversed Gateway in 2154, when beginning their journey into the Forge in search of the Syrrannites. (ENT: "The Forge")
In the script of "The Forge", Gateway was described as "an epic expanse of red sand".
T'Pol specifically pointed out the possibility that Surak's entrance in the forge might not have occurred as believed because of his original writings