The United States Botanic Garden (USBG) is a botanic garden on the grounds of the United States Capitol in Washington, D.C., near Garfield Circle. The Botanic Garden is supervised by the Congress through the Architect of the Capitol, who is responsible for maintaining the grounds of the United States Capitol. The USBG is open every day of the year, including federal holidays. It is the oldest continually operating botanic garden in the United States.