Hey Bla, could you make a road from Kaeshar to approximately the area circled? You can probably continue off the road leading to the observatory and remove as many trees as needed since that forest is pretty dense. Also, unless you are going to go around the mountains by going northwest, just make as many tunnels as needed. Or heck, make a straight tunnel through a section of the mountains.
I had also thought of making a rail route over there, but considering that the route to Kaeshar used like 500 something iron and a week or so ago (when I asked about using iron for the bridge), there wasn't even 200 in collective storage, so that can wait.
I already have an advance base in the nearby cove (its hidden by the trees in the image) and I'm planning on developing the area further. Not to mention that there are lots of caverns, at least two ravines, an epicially big cavern to the north beyond that sandbar and an extensive (bigger than what I have in Kaeshar) abandoned mine in that region with the swamp and continent.
I'm thinking of eventually putting in some Mesoamerican style ruins in the jungle itself.