City of Aurora
Starting from the Shifting Sands entrance, move downwards all the time and turn left by the second banner . The silver key has been hidden behind the rocks .
From the market place , head along the path beside Shackleram's House to the very top of the hill and turn right .
This way you will reach a stone arch . From it, jump onto the roof of the building below  and from between the houses and towards the floating key.