The formation of the city itself started later, on lands donated by Paulino Speratti for the construction of a church, a square, a school, the seat of the municipal authorities and the office of the peace judge.

General Las Heras born as game October 25, 1864, with the main Spanish settlers, Italian, English, French and German.

Created the same jurisdictional boundaries were established by decree in February 1875 and they are the parties of the Slaughter, Morón, Villa de Lujan, Navarro, Lobos and Cañuelas.

At that time Mr. Paulino Speratti through his wife Casilda Villamayor, donates land for construction of the church, a square, a school, the seat of the municipal authorities and the Magistrates Court.

This system expires with the creation of the law of September 11, 1884, where the judicial functions of the administrative and political performed the Justices of the Peace are separated, initiating stage of municipal mayors and occupying the first position Don Juan Zamudio person nicknamed "the father of the poor" and that anyone who approached his stay was well received and helped generously.