The Iron Age is the fourth and final age after the Bronze Age in Age of Empires. To reach this age, 1000 food and 800 gold is required. This age is often charaterized by military conquests and economic expansion as well as the difference between victory and defeat. During the Iron age, players often are limited by the comparatively high cost of minute unit upgrades, such as Centurions and Heavy Horse Archers, which require almost as many resources as Wonders. Therefore, it is often in this age in which a player will invest in a more specific strategy. Wonders are available to construct in this age.

Buildings which are available in Iron Age

• Wonder
• Fortification
• Guard Tower
• Ballista Tower

Units available in Iron Age

• Horse Archer at Archery Range
• Heavy Horse Archer at Archery Range (Prerequisites Chain Mail for archers)
• Elephant Archer at Archery Range
• Catapult at Siege Workshop
• Ballista at Siege Workshop
• Heavy Catapult at Siege Workshop (Prerequisites Siegecraft)
• Helepolis at Siege Workshop (Prerequisites Craftsmanship)
• Long Swordsman at Barracks
• Legion at Barracks (Prerequisites Fanaticism)
• Scythe Chariot at Stable (Prerequisites Nobility) (Rise of Rome)
• Heavy Cavalry at Stable
• War Elephant at Stable
• Cataphract at Stable (Prerequisites Metallurgy)
• Armoured Elephant at Stable (Prerequisites Iron Shield) (Rise of Rome)
• Phalanx at Academy
• Centurion at Academy (Prerequisites Aristocracy)
• Heavy Transport at Dock
• Trireme at Dock
• Catapult Trireme at Dock
• Fire Galley at Dock (Rise of Rome)
• Juggernaut at Dock (Prerequisites Engineering)