Washington, D.C., formally the District of Columbia and commonly referred to as Washington, the District, or simply D.C., is the capital of the United States founded on July 16, 1790. The city shares its name with the U.S. state of Washington located on the country's Pacific coast.

The District is located on the north bank of the Potomac River and is bordered by the states of Virginia to the southwest and Maryland to the other sides. The city has a resident population of 601,723; because of commuters from the surrounding suburbs, its population rises to over one million during the workweek.

The centers of all three branches of the U.S. federal government are located in the District, as are many of the nation's monuments and museums. Washington, D.C. hosts the headquarters of the World Bank, the International Monetary Fund (IMF), the Organization of American States (OAS), the Inter-American Development Bank, and the Pan American Health Organization (PAHO). The headquarters of other institutions such as trade unions, lobbying groups, and professional associations are also located in the District.