Dont know how to show you on the map but can try to explain. On the road from the mountain monestary going toward Treomar (the long way around) in the dark forest there is squigly winding road to the right, just before reaching Treomar. You will see some stairs leading up into the mountains. Right at the top you will find the Treomar Beacon. There is a glider you can get onto that will carry you to the tower.
Map:
There should be a long stairway.
As you may guesstimate from the marked screenshot the stairway / trail starts way northwest from the glider. (the T junction on the right side of the arrow.)
As often, i found it a couple of minutes after posting. 
Thanks!
Thanks!







