Game of thrones season 3 trailer

[McGrupp]

Originally Posted by Gogan

One thing I'm still confused about though... why are Snow and the Wildlings trying to get south? Are they trying to assault Castle Black, and if so why? Or are they trying to open the gate to let the rest of the Wildlings through? Is this all just to flee from the white walkers, or is there some other motivation? What's their end game here?

Multiple reasons:
Escape the white walkers, Gain freedom, Take over the wall. Not sure if they'll get to the climax in this season, but it is unforeseeable and amazing.