[ericthered]

The Yrth maps tend to be somewhat stylistic. I expect every trade town has a wide path leading to it, and I think three of them are in a wonderful location to trade with megalos: they seem to line the southern border of it.

On the other hand, the locations of the trading towns changes depending on the maps you use. This is particuarly flagrant in the Sahud-Zarak Border. Durinel and Ekarriel are in two very different places on the two maps. And if you accept the Sahud maps, Western Zarak has no trading town. If you accept the Zarak maps, Sahud is limited to a single trading town, despite sharing border as long as the Megalos-Zarak Border.

I would not put roads through the mountains. The trading towns are on the edge of dwarven territory, and the dwarves have less that no motivation to build nice surface roads through their territory.