Jaime will arrive at Riverrun, the castle historically occupied by the Tully family (Catelyn Stark's childhood home).
He's going to meet with the Blackfish, a.k.a. Brynden Tully — Catelyn's uncle and a renowned fighter who has taken his castle back from the Freys.
The Blackfish was present at the Red Wedding, but happened to go outside to relieve himself right before the massacre began.
Jaime, newly relieved of his duty as Lord Commander of the Kingsguard, has been charged with laying siege to Riverrun and ousting the Blackfish.
Jaime won't be setting out on his own. Bronn is back! The season five bro-team will be reunited again in the Riverlands.
The Freys are going to use Edmure Tully, the Blackfish's nephew, to force him to yield. Here we see a Frey holding a knife to Edmure's throat.
This Frey (possibly Lothar, Walder's son) looks concerned. Some fans believe we're going to see a resurrected character in the Riverlands ...
That's right. We could be seeing Catelyn Stark's zombified self, known as Lady Stoneheart in the books. People think she may appear due to the converging plotlines happening in the Riverlands, which is her turf in the book series.
BONUS: This shot is from one of the season six trailers, and not the episode seven one, but here we see Brienne and Pod inside Riverrun. Sansa sent them to bring the Tully army north, so we can expect a Jaime and Brienne reunion.
Here is a mysterious scene we can't confidently place. The grassy area looks like it could be the Riverlands, and the limping foot is moving through a pile of dead bodies.
Could this be The Hound's return? We know the episode title "The Broken Man" ties into the fan theory about his survival, so perhaps next week will be the episode when it finally happens.