The Centennial International Exhibition of 1876, the first official World's Fair to be held in the United States, was held in Philadelphia, Pennsylvania, from May 10 to November 10, 1876, to celebrate the 100th anniversary of the signing of the Declaration of Independence in Philadelphia. Officially named the International Exhibition of Arts, Manufactures, and Products of the Soil and Mine, it was held in Fairmount Park along the Schuylkill River on fairgrounds designed by Herman J. Schwarzmann. Nearly 10 million visitors attended the exposition, and 37 countries participated in it.