On 15 June 1850, a group of 34 men (commanded by Andrés Zapata, Gaspar Salazar and Antonio Ramírez) met with Colonel Juan Manuel Maldonado to give the news that they had created a pass point at Piedras Negras, to the right of the Rio Grande, south of Fort Duncan; and having given it the name of: Nueva Villa de Herrera. Later on it would be renamed Villa de Piedras Negras. In Otto Schober's "Breve historia de Piedras Negras," the local historian points out that the 34 men in in question were repatriates (Mexican Americans) that arrived on June 15, 1850 in what was then called "Colonia Militar de Guerrero en Piedras Negras."
Due to the discovery of huge deposits of coal at the region, in 1881 a railroad track was begun, finishing in 1883. With this construction, the regional economy flourished and on 1 December 1888, it was granted the status of city; this time with the name of Ciudad Porfirio Díaz. After the fall of Diaz in 1911, the city reverted back to Piedras Negras, Coahuila
