There are 48 spaces in your city center for wharves. A wharf allows you to buy and sell a specific type of good within your city.

In a new city, the wharves must first be opened by spending an Imperial Point. Once a wharf is open, you can select the type of good to be held at that wharf. Once a type of good is chosen, only the Praefectus Urbis or City Councilors may change the type of good.

If a wharf is full, you must upgrade it or export some of the goods from your city in order to be able to sell more.