When They Were Last Together: The Kingsroad (S1E2)
What Happened Then: Jon kissed Bran (who was in a coma) goodbye, telling him they could go out together beyond the Wall. Their paths came agonisingly close, but they never reunited.
What Happens Now: Bran is the Three-Eyed Raven, and can further confirm the shocking news Jon has just received - that he is Aegon Targaryen.