One Franklin Square is a high-rise building at 1301 K Street NW, in Downtown Washington, D.C., United States.

Downtown is the central business district of Washington, D.C., located in Northwest D.C. It is the third largest central business district in the United States. The "Traditional Downtown" has been defined as an area roughly between Union Station in the east and 16th Street NW in the west, and between the National Mall on the south and Massachusetts Avenue on the north, including Penn Quarter. However, nowadays, Downtown D.C. usually refers to a larger area, as the DC Office of Planning states:…most residents, workers, and visitors think of Downtown in a broader sense — including areas as far north as Dupont Circle, as far west as Foggy Bottom, and as far east as Capitol Hill. Only about half of the central city workforce is located within the city’s traditional Downtown.