D.C. Code § 1-107
That portion of the District included within the limits of the City of Washington, as the same existed on the 21st day of February, 1871, and all that part of the District of Columbia embraced within the bounds and constituting on February 11, 1895, the City of Georgetown (as referred to in the Acts of Congress approved February 21, 1871, 16 Stat. 419, ch. 62, and June 20, 1874, 18 Stat. 116, ch. 337) shall be known as and shall constitute the City of Washington, the federal capital; and all general laws, ordinances, and regulations of the City of Washington are extended and made applicable to that part of the District of Columbia formerly known as the City of Georgetown. The title and existence of said Georgetown as a separate and independent city by law is abolished. Nothing in this section shall operate to affect or repeal existing law making Georgetown a port of entry, except as to its name.
D.C. Code § 1-107