The capital of United States is Washington D.C., which was founded 7/6/1790. Washington D.C. has been the capital since 7/16/1790.
Although Washington D.C. is not the largest city in United States, it functions as: Houses the White House.
Washington D.C. is located at 38.9072, -77.0369, at an elevation of 72 ft.
Source: https://flic.kr/p/9X1zuW