Trade in Foundation is done with neighbouring cities that cannot be visited. They will trade resources that have been designated for purchase or sale in the Book under the Resources section of the Trade tab.
Each city is seeking to purchase four resources from the village and sell five back. Traders will pick up and leave traded items in a granary or warehouse that has been assigned to store the resources in question; any goods in a production building, a market, or in transit to a building are considered unavailable for trade.
The fortified haven of Castle Harbour trades in wonders of distant realms.
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Castle Harbour is the sixth city to become available for trade, it can be unlocked with 15 . The city is aligned with kingdom.
It is allied with the kingdom.