Civilizations learned to build ships and venture out onto the sea to fish and trade. Port cities that had access to the sea for commerce and food gathering became prosperous economic centers, but the sea also harbours a dangerous secret. An old shanty sings of giant sea monsters lurking in the abyss, lost shipwrecks, and sunken treasure.
Docks are additional resource production Buildings that produce food as well as gold when upgraded to Port.
Docks are terrain-limited structures, and can only be built in LANDS next to the sea.
Docks can be upgraded to Harbours which then can be upgraded to Ports. Each upgrade increases food production per hour. Upgrading to Port unlocks gold production.