Not really useful just wanted to find a way to get up there.
Notes, you need two people and atleast one needs to be an engineer (you need engineering to get past the first step) and only certain classes can do this.
Basically you need to get up here.
(Don't have pics/video of me getting up here and my friend is currently offline so can't do it again right now)
Getting here requires two people both of which need to have a charge like ability (have a warrior spell reflect death grip will probably work) and one of them needs to be able to summon a pet and select it's location (like treants etc)
So you get to the location at 0:25 of this video [ame="http://youtube.com/watch?v=4z8hgJ6Nu3Q"]YouTube - On top of Stormwind Wall[/ame]
(I'll make a vid or maybe post some screen shots tomorow if my description isn't enough) Then you duel your friend, then basically you work your way up the hill by summoning your pet at places that looks like you will be able to stand/walk around and putting them on stay instantly (keybind it) then having the other charge the pet and then the person who summoned the pet charge them. (not many classes can do this, my friend was a dual specced balance/feral druid) You can also use explosive decoys as the summoned pet, but they have a smaller range... I think.
Here is the path I use
(lolpaint)
Won't be exact but you should get the picture. (the green circles are where you summon the pets)
So basically once you are up to the bit of the first screen shot you will need rocket boots + some form of slow fall, noggenfogger + parachute cloak should do it. Now just aim (not the easiest thing to do) and use your slow falls/rocket boots.
Ontop of cathedral:
In the other stockades place:
Hope this isn't a repost and if there is an easier way then... dflgkjfdgl;fjgl
Also incase anyone is wondering in the first screenshot the mage got there by being summoned by a warlock that I summoned through RaF (although I think demo locks have a charge while in meta? So they could probably get up there aswell to do summons.
One last thing, I was thinking you might be able to get there from the mountains to the east of Stormwind (the ones with the lake that has the pleacebloom fishing spot.) and rocket boot jumping from them.