if your go for the stealth option take the right under the bridge and then there are nets to climb and drop too all the way to the gem you will have to fight a few but not many.
for the kegs i found i missed 3 of them but got them eventually. 1 is on the rocks next to the entance on the bottom of your base, exit the gate and go to the rocks on your right there will be a gap which leads you to the barrel.
one in the stream by the lumber mill it is just in the middle of the water.
one in the settlement near caldberg it is next to a house on the cliff edge.
also there are two under the bridge for caldberg.
Hope this helps.
take a bow son, take a bow.
Andy Gray on Gerrard.!