Washington, D.C., officially the District of Columbia (also known as D.C.; Washington; the Nation's Capital; the District; and, historically, the Federal City) is the capital city and administrative district of the United States of America. Washington, D.C. is part of the Baltimore-Washington Metropolitan Area, which also includes parts of Maryland, Virginia, and West Virginia. It should not be confused with the U.S. state of Washington, located in the Pacific Northwest.
The District of Columbia is a federal district as specified by the United States Constitution with limited—and sometimes contentious—local rule. Similar to the position of the 13 American colonies under the British Parliament, the District is ruled "in all cases whatsoever" by the U.S. Congress, while nevertheless going unrepresented in that body. (See and compare the Declaratory Act of 1766 by the British Parliament and the "District Clause" – Article I, Section 8, Clause 17 – of the American Constitution; see also the American Declaration of Independence, and "The American Crisis, Number 1," December 23, 1776, by Thomas Paine). The land was taken from both the states of Virginia and Maryland, though only the Maryland portion remains part of the district. The population of the District of Columbia, as of 2003 U.S. Census Bureau estimates, is 563,384. If Washington, D.C. were considered as a state, it would rank last in area behind Rhode Island, and 50th in population ahead of only Wyoming.
The centers of all three branches of the U.S. federal government are in Washington, as well as the headquarters of most federal agencies. Washington also serves as the headquarters for the World Bank, the International Monetary Fund, and the Organization of American States, among other international (and national) institutions. All of this has made Washington the frequent focal point of massive political demonstrations and protests, particularly on the National Mall. Washington is also the site of numerous national landmarks, museums, and sports teams, and is a popular destination for tourists.