Capitol Hill, in addition to being a metonym for the United States Congress, is the largest historic residential neighborhood in Washington, D.C., stretching easterly in front of the United States Capitol along wide avenues. It is one of the oldest residential neighborhoods in Washington, D.C., and with roughly 35,000 people in just under 2 square miles (5 km2), it is also one of the most densely populated.
As a geographic feature, Capitol Hill rises near the center of the District of Columbia and extends eastward. Pierre (Peter) Charles L’Enfant, as he began to develop his plan for the new federal capital city in 1791, chose to locate the “Congress House” (the Capitol building) on the crest of the hill at a site that he characterized as a “pedestal waiting for a monument”. The Capitol building has been the home of the Congress of the United States and the workplace of many residents of the Capitol Hill neighborhood since 1800.