Iron

Iron is one of the five main resources in the game, next to food, lumber, stone, and gold.

Uses
Iron is consumed by the following actions:
 * Construction of buildings
 * Construction of fortified units
 * Researching technologies
 * Troops training

Acquisition
Iron is produced by Ironmines, but it can also be won on the Wheel of Fortune, or farming NPCs for resources. If done correctly, large amounts of iron can also be acquired by trading with resource (i.e. buying a resource for a cheap price and selling it for a more expensive price).