sup /tg/

I want to run a game where the PC's are traders on the silk road around year 1200. (Think Marco Polo)

Problem is, I can't find a system that includes extensive trading and traveling mechanics. The game would be divided into traveling around, fighting bandits, crossing borders, etc. and actually trading goods to make a profit. Obviously, it would be a rather sandboxy game since there were many paths and cities between both ends of the silk road.


Any suggestions as to which system I should use? Opinions and advice are welcome too!