Left-most Technologies (Cataphract, Archer, Cavalry, Feudalism, Monotheism, Science, Catapult, Galley, and Warrior) are base tech. You start with them. You may research one new technology every turn. You must have all technologies leading to a technology to have it (e.g. to get Raider, you need Galley, Warrior and Longship). I recommend colouring the lines to a technology to show what you have completed. Time taken to complete a concept technology/unit technology/building technology: 3 years (15 days)
