|Required for||Units: Swordsman, Longswordsman, Samurai, Berserker, Frigate, Ship of the line, Legion, Kris swordsman|
Basic strategic resource. Used by powerful early-game front-line units and middle-game ships.
As the first strategic resource revealed on the map along with Horses, Iron is very important for planning your initial expansion. Research Iron Working (Bronze Working in Brave New World), then look for the newly revealed resources and try to settle near them.
Iron is required for the strongest early-game front-line units and also for Frigates, an important middle game ship. This makes it a vital resource for all early-game expansionist civilizations, like the Huns.
Iron is found practically everywhere, which makes it a relatively easy-to-access resource. Still, it's more common in out-of-the-way locations, such as Tundra and Snow terrain. Iron is exploited via Mines, which makes it easy to access.
Like all strategic resources, it nets a good increase in Production for the tile. Its unique benefit is to allow construction of the Forge in a nearby city. This building grants a building bonus for all land units (not only mounted units), which makes cities with access to Iron natural military training centers. Take advantage of this by constructing military training buildings like the Barracks in the city, as well.
Iron is one of the most important metals in human history. It is used for construction, for military weapons, and for tools. The first iron used came from pure deposits found in meteorites, and by the 2nd millennium BC some cultures had learned how to extract it from ores found in mines. Iron continues to be an extremely important material in the modern era, though it is most often used in its steel alloy form. Remember that iron is a strategic resource, and thus it is consumed as you construct the associated units and buildings.