Presidente Hayes is one of the seventeen departments that, together with Asunción, Distrito Capital, form the Republic of Paraguay. Its capital is the city of Villa Hayes under a law of the National Congress of 1999 in replacement of Pozo Colorado. It is located to the south of the western region of the country, bounded on the north by Alto Paraguay, on the east by the Paraguay River that separates it from Concepción, San Pedro, Cordillera, Central and Asunción, Capital District, on the south by the Pilcomayo River that separates from Argentina, and west with Boquerón. With 121 075 habs.
In 2017 it is the fourth least populated department -before Ñeembucú, Boquerón and Alto Paraguay, the least populated-, with 72 907 km², the third most extensive -behind Boquerón and Alto Paraguay- and with 1.68 inhabitants / km², the third less densely populated, ahead of Boquerón and Alto Paraguay, the least densely populated. The department was named in honor of the President of the United States Rutherford B. Hayes, who was an arbitrator in the boundary dispute between Paraguay and Argentina after the War of the Triple Alliance.