5 December 1964: broadcast of "Day of Reckoning", third episode of the story we now call The Dalek Invasion of Earth. This is the fantastic episode with Jenny, Barbara and Dortmun fleeing across London to Francis Chagrin's amazing music, followed by Dortmun's last stand against the Daleks.
ii) date specified in canon
5 December 1920: Kathy Nightingale is transported to Hull from 2007 by the Weeping Angels. (As seen in Blink, 2007.)