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The Assembly Plant is the unique building of the German civilization.
Strategy[]
Compared to the Factory it replaces, the Assembly Plant allows the city it is built it to convert an additional 2 citizens into Engineers. In addition, the production speed of the Assembly Plant is increased by 50% if the city has access to Coal 
.
Civilopedia entry[]
A factory is a building or complex of buildings where workers manufacture goods. In many cases the goods are manufactured using an "assembly line" style of production in which individual parts are added to the product by a number of workers, each of whom performs his or her actions in sequence as the product moves down the production line. The factory also may include a warehouse to store parts as well as the finished products.
The Venice Armory is the first known factory in history. Founded in Venice, Italy, in the twelfth century, it produced ships using an assembly-line style of production. During the Industrial Revolution in the eighteenth century, factories sprang up across Europe and North America, with the earliest concentration in the British Isles. The United States greatly streamlined the process during the early twentieth century.
Although a relative latecomer to manufacturing, by the early twentieth century the German factories were among the most efficient. During the First and Second World Wars German plants built thousands of tanks, planes, and other war materiel under horrendous conditions and in the face of concentrated Allied bombing attacks. Moving into the twenty-first century the German factories remain among the best in the world.