The United States declared independence in 1776, but Washington, D.C., did not officially become the nation's capital until 1800. In fact, the US went through eight other capital cities before settling on Washington, D.C. The original capital of the US was Philadelphia, Pennsylvania, from 5 September through 26 October 1774, during the meeting of the first Continental Congress. Another Pennsylvania city is known for being the US capital with the shortest tenure – Lancaster, which served as capital for just one day on 27 September 1777, when the Congress had to leave Philadelphia to flee from British troops.
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