Ok i found something like this but its "Different" so here it is.
At the begining of Warsong Gultch this is kinda usefull because u can get to the Running speed Chest before anyone else so you just get out there before anyone thats what this is for.
ok it only works in this region.
I Rotated color so Arrows can see the spots where you can mount up.
Right from that wall with that window and right under that Latern.
You can mount up there