I have recently picked up King of Dragon Pass, and I like exploring the strangeness of thin setting. Many of the things either make sense to me or I'm willing to try and figure them out, or I found some guidance online for the more mechanical things I'm less willing to try and try again, but I cannot figure out how to **establish a trade route**.

I have sent caravans with the goal of “establish trade route” to clans near and far, allied or owing favours or friendly, before and after building a shrine to Issaries, and yet no trade route was ever established.

What are the necessary conditions to establish a route? If they are met, how do I improve the chances that it actually happens?