Trade is an essential part of the game and for most cities a primary source of income. Pharaoh has a sophisticated trade system, allowing the player to manage the flow of commodities into and out of the city.
Trade begins by establishing a trade relation with another city. For this, a map of the known world is accessed, allowing the player to select a city, see what the city will sell and buy, and purchase the rights to trade with a city. The farther away a city is from the player's city, the more expensive the trade right routes will be. Some cities will not offer to trade right away, but must be given gifts or assistance to open up their own trade route.
Once a trade route has been opened, the trade city will send traders to do business. Trade over land appears in the form of a caravan which will walk into the city, sell or buy their commodity, and then depart. Trade over water is slightly more complex, as it involves constructing a working dock.
Docks allow trade ships from other cities to tie up and send agents into the city to buy or sell goods. To prevent back-ups at the dock, cities with multiple trade routes should have two or more docks. Docks also should not be located too far away from the storage yards where goods are kept, or the ship's agents will have to travel across the city and delay the vessel's time at the dock.
Excessive importing of a product can be prevented by instructing merchants to only deliver products to city storage yards if those storage yards have not exceeded a given stockpile. Similarly, exports can be limited so that the city does not run out of a given commodity. Additionally, instructions given to each individual storage yard can ensure that trade deliveries to one particular location are quickly distributed over the city, which is important for trade by water as cities usually only have one suitable site for docks.
Trade cities will only trade a maximum amount of goods per year, with this level raised depending on events in the game such as lending assistance to a city or having the God Ra encouraging trade partners to do more business. Trade routes may also be disrupted or even cut off by sandstorms, war, or the Nile river becoming too turbulent to travel.
The player can also order the city to stockpile a commodity by temporarily, or permanently if the good is not needed, preventing export and consumption. This is useful e.g. if you need to satisfy a kingdom request for the good and couldn't otherwise reach the level of supplies necessary in time. Short-time stockpiling is generally not harmful for a well-managed city, do however remember to turn stockpiling off once the need has passed.