Outer door

The outer door was the first of the two doors of the TARDIS, as used by the First Doctor. Through the outer door was the exterior entrance chamber, followed by an inner door which led to a fourth dimension beginning with the control room. (COMIC: The Secrets of the Tardis)

Jack Harkness clung to the outer door of the TARDIS as it traversed through the Time Vortex from 2008 to 100,000,000,000,000. (TV: Utopia)

Initially, the Doctor believed that one could not open the doors by snapping one's finger. However, he learnt from River Song that he would do so in his future. Indeed, following their encounter, the Doctor successfully opened the doors with a snap of his fingers. (TV: Forest of the Dead)