Detroit

Future!Dean tells Dean that Sam was in Detroit when he gave Lucifer permission to possess him^{5.04 The End}

Lucifer informs Sam that he will eventually say yes to him and become his vessel ^{5.10 Abandon All Hope}
Sam later becomes his vessel, but he eventually regains control and throws himself, Lucifer and Michel in the Cage^{5.22 Swan Song}

Notes

In spite of Lucifer being correct in his prediction, things did turn out differently than Zachariah's vision illustrated. For one, not everyone was infected with the Croatoan Virus like they were in 5.04 The End, the Angels didn't bail out and leave Heaven. But, there were many similarities between the episodes: 5.04 The End and 5.22 Swan Song.