Jared Padalecki joked on Twitter that, during the scene where Sam slaps Dean's face to wake him up, Jared purposely messed the scene up to be able to slap the director - Jensen - in the face over and over. Jensen backed him up, saying it took a few takes to figure out what Jared was doing.
In the scenes in Hell's Throne Room, the young demon on Crowley's right handling documents was played by Mark Sheppard's real-life son, Max.
Though this is the third episode in the season, it was filmed first to allow Jensen Ackles to do the prep for directing the episode without the added stress of acting. He was able to do the prep over the summer and then get the episode out of the way so that he could focus on acting.
The name of the gas station Castiel and Hannah stop at is called "Li'l Levi's". This was a shout-out to Jensen Ackles' nephew.