The Classical Age is the second age a player can reach in Rise of Nations, and the first age available to research.
After advancing to the Classical Age, players are given many new options, compared to the Ancient Age. In this age, Metal and Knowledge first appear, Mines and Universities becoming available to gather these new basic resources. Recruitment and military strategy are greatly expanded with the Stable, Siege Factory, Fort, and Tower, while Barracks units see their first upgrade unlocked. The first enhancement buildings are also unlocked: Granary, Lumber Mill, and Smelter, and the first Wonders can be built.