Washington, D.C., United States

Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is located on the east bank of the Potomac River, which forms its southwestern border with Virginia, and borders Maryland to its north and east. The city was named for George Washington, a Founding Father, commanding general of the Continental Army in the American Revolutionary War, and the first president of the United States, and the district is named for Columbia, the female personification of the nation.

Washington, D.C., represents the southern point of the Northeast megalopolis, one of the nation's largest and most influential cultural, political, and economic regions that runs along its northeastern coast from Boston in the north to Washington, D.C., in the south and also includes New York City, Philadelphia, and Baltimore. As the seat of the U.S. federal government and several international organizations, the city is an important world political capital. It is one of the most visited cities in the U.S. with over 20 million annual visitors as of 2016.