So how much communication is there between Peloria and Ralios (or Dragon Pass and Ralios)? The Western Rockwoods (and their associated ranges the Mislari and Nidan Mountains) are a high mountain range, with few passes lower than 2200 meters (and most significantly higher). Many of the peaks are over 4000 meters high and one, Top of the World, is said to be 10,000 meters in elevation.
There is one major exception – Kartolin Pass between Dorastor and Ralios is at about 1500 meters and is broad enough for caravans, wagons, settlers, and armies to travel through it to Ralios. In the First Age, colonists (and later armies) from the Second Council went over this pass to settle in East Ralios and Vesmonstran. The dwarves built a great stone fortress to guard the pass, and it proved impregnable even for Arkat.
However, with the end of the First Age, Dorastor was left a poisonous waste and Kartolin Pass ceased to be a means for communication between Peloria and Ralios.
The Orlanthi settlements in Ralios grew despite being largely cut off from Dragon Pass. Fliers traveled between the East Wilds and Dragon Pass, and the Nardain Society had special Rune magic (now mostly lost but for Guided Teleportation) that facilitated long distance communication beween Ralios and Dragon Pass.
The EWF greatly increased communication between Dragon Pass and Ralios. Magicians, warriors, and leaders rode dragons and wyrms to fly from Dragon Pass to Ralios, sometimes carrying goods, crafters, and others. Influences from Dragon Pass grew and dragonic magic was practiced here.
With the collapse of the EWF, communication between Ralios and Dragon Pass nearly ceased. Only the most powerful of magicians or intrepid of adventurers went over the Western Rockwoods in the Third Age. A yearly caravan from the Lunar Empire now travels through Kartolin Pass with the permission of the broo demigod Ralzakark, and continues on to Safelster.
Now this is primarily about humans, as the trolls of Halikiv are perfectly about to communicate with the trolls of Dagori Inkarth and the Shadow Plateau. But that is fodder for another post.