Trade can be an extremely profitable activity, but you can only trade when there are goods available.
These are distributed across the map to accurately reflect the pattern of medieval trade. Some provinces have no trade goods at all.
The larger and grander the Merchant involved in trade the greater the potential profits.
One of the four parts of income in medieval economy is trade, the first advance is a ‘ Trade Post’, which can only be built after a fort in produced in a province.
The diagram on the left shows the advancement, costs of production, build times and other buildings that are required to build the trade advance.