Construction
Prerequisite Techs: None
Leads to Techs: Engineering
Unlocks: Colosseum,The Great Wall, Bridges
Horseback Riding
Prerequisite Techs: None
Leads to Techs: Chivalry
Unlocks: Horseman, Companion Cavalry, Stable, Circus
Iron Working
Prerequisite Techs: None
Leads to Techs: Metal Casting
Unlocks: Swordsman, Mohawk Warrior, Roman Legion, Armory, Heroic Epic, Iron
Mathematics
Prerequisite Techs: None
Leads to Techs: Currency, Engineering
Unlocks: Catapult, Roman Ballista, The Hanging Gardens, Courthouse
Optics
Prerequisite Techs: None
Leads to Techs: Compass
Unlocks: Floating Gardens, Lighthouse, Embark
Philosophy
Prerequisite Techs: None
Leads to Techs: Theology, Civil Service
Unlocks: Mud Pyramid Mosque, Temple, National Epic, The Oracle, Burial Tomb, Research Agreement
