Basic troop-training building of the Ancient Era.
- +3 Science and +1 Culture from Regimental Tradition Policy
Barracks provide experience for military units constructed in the city, which can be used to give the units promotions that make them more effective in battle. Any unit produced in a city with a Barracks will immediately be ready for a promotion.
Barracks are only the first in a line of buildings that improve a city's military units. Eventually you can chain together Barracks, Armories, and Military Academies. Though expensive and time-consuming to put together, this creates a city that produces veteran units right off the bat, cutting casualties in the field considerably.
Peaceful or defensive empires don't always need Barracks in every city immediately. Building these is time better spent on cultural endeavors. For more martial people, it's wise to have these in every productive city so that a force can be marshaled in far less time.
Barracks reduce Crime in the city which it is built, and gain extra Production when coupled with the Arena, making them useful even in peacetime. The barracks also increases your Supply Cap by 1, allowing you to field a larger army.
A Barracks is needed if you want to create a Heroic Epic. This is a National Wonder that gives +10% in combat to any troops constructed in the Heroic Epic's city. That's a massive benefit. You should generally build one in every city and your Heroic Epic in a place with high Production. Make sure that it's your primary military city, and make sure to give it all possible military training upgrades through the Armory and Military Academy.
Barracks are military buildings that house a country's professional soldiers. In addition to providing food and shelter for the soldiers, they provide training and medical facilities, as well as military jails, vehicle maintenance, and so forth.
Barracks are important to a civilization's happiness and well-being. They promote cohesion among the ranks, improving the soldiers' chances of success in combat, and they control direct contact between civilians and soldiers, limiting the friction that is almost universally caused when the two groups intermingle overmuch.