Hey,
So well.. yeah.. how did I find this one.. well we where jumping around at the Dredge Fractal right at the beginning.. go left. And jump towards the wooden stuff. You can pretty high and at some point you can jump on a ledge which brings you to a dead end tunnel.. well I thought.. because I could walk trough the wall and BAM, fell out of the level into the whole fractals map.
I can try to post some screenshots tommorow
. But maybe some people can try it out themselves. And report it, it was funny to go to the Fight of Ascalon and turn in to a Charr almost the whole Fractal run :p.