actually, I'll just describe it, because Ii seem unable to post the picture (I'll eventually ask shadow when I meat him at school.
In the map, A Split Road, (west of Hennessey {I think that's how it's spelled}), if you go towards Kerning from FSI, at the top most part of the road, inline with the would be kerning portal, If you walk up at certain points, you can go through the cliff... if that makes sence if it doesn't, I'll e-mail it to someone.