Quote Originally Posted by Velox View Post
There is a road in the Sylphlands that leads to Ala Mhigo, so we can assume at some point in the story we have to retake it back from Garlean control. At that point we will be on the doorstep of the empire.
The road is actually already clear but SE has not released the road into Ala Mhigo yet.

The City-State captured the Castrum guarding the path into Ala Mhigo back in 2.0 storyline and it is currently under Twin Adder and Sylph forces control. They're probably modifying the Castrum now into a Twin Adder Base.