The Forbidden City was designed and constructed in the style of traditional Chinese palace architecture, with a focus on articulation and bilateral symmetry to represent equilibrium. Classical Chinese architecture, particularly those of the rich, often stress width rather than height. This allows for large halls that can house ceremonies as well as palaces. The Forbidden City was built over a period of almost 150 years, from 1406 until its completion in 1644. It was the home of several generations of the imperial family, but also served as a museum after it was abandoned by the emperor. It is said that Emperor Shizuoka ordered the construction of the city to celebrate his retirement after fifty-five years on the throne. However, this explanation isn't very convincing since there were already many cities across China that followed this style of building. More likely, the decision to build the city was made to demonstrate the prosperity of the empire after many years of war. The fact that it was never used as a residence shows that the emperor didn't want to be tied down by permanent residency. The Forbidden City was built using local labor forces because no outside architects or engineers were allowed inside the walls. They did, however, hire many foreign workers through contracts to avoid conflict with other countries. The name "Forbidden City" comes from the fact that during the early years of its existence, it was not open to visitors.