A large trade route I like is what I call the Salt and Iron loop. Works great for a Nord at peace with Vaegirs
1. Start in Curaw, buy cheap Iron.
2. Go to Wercheg, sell Iron buy Salt
3. Go to Sargoth sell Salt by Flax (Make sure it is under 90 though, sometimes it spikes)
4. Go to Tihr sell Flax buy more Salt
Take Salt back to Curaw.
Now if you are in major times of peace you can add Swadia onto the loop thoug you will have some empty stops. Starts right after Salt at Tihr
5. Go to Praven, sell Salt, maybe buy Ale if it is low, if not ride on (Also good chance of their being a feast so play in a tournament or 3
6. Go to Suno, sell Ale if you have it, buy cheap Oil and Wine
7. Go to Dhrim, sell Oil and Wine, buy Iron
8 Go to Reyvadin, sell Iron and possible buy some food as they will often have cheap dried meat
9 Go to Curaw and get the Iron.
Whats great about this route is has some simple big profit items and also hits three capital cities where Kings are likely to be holding feasts.