It's cool, I had a save file handy right after the conversation with Duncan & Cailan. I found it amusing actually, I ran up to the crevice in the cliff to get a closer look at the surrounding area and it ports you there. Reminds me of my WoW days where me and a friend from IRL would hack/wall walk our way into areas that were still in development (Caverns of Time pre BC for you WoW players here,) GM Isle, Zul-gurub beta.... *sigh* good times.
But yeah, here's the exact cliff (complete with crevice) and an image of the map.