Lieutenant Colonel Lorenzo Vinter, chief of the 5th Cavalry Regiment, under the command of General Julio Argentino Roca (who was the then Minister of War and the Navy) established a fort named Fort General Roca at the spot known as Fisque Menuco on September 1, 1879.
Approximately 5 years later, the military occupation gradually adopted an agricultural profile, through the measurement of farmlands and orchards, ending up with the construction of an irrigation channel that started at the Neuquén River and distributed its waters through “Canal de los Milicos” (Channel of Military Men), so called because it had been dug by prisoners, soldiers and native Americans from Fort Roca. This event happened simultaneously with the arrival of groups of immigrants (mostly French and German), who began to settle down in the proximity of the fort, which was already becoming a major center of supplies for different locations in Neuquén and Río Negro.
In 1907, after a big flood in the area which had taken place in 1899, the Irrigation Cooperative was forced to reconstruct the irrigation channel, which was finally part of the national irrigation network as from 1921. Not only did the flood affect this area, but also the City of Viedma. For such reason, the capital was moved to Choele Choel. Thus, the inhabitants of Fort General Roca and Viedma were sheltered in the highest area of the cliffs, at a spot that came to be known as El Campamento (the Campsite), where a neighborhood lies today, to the North of Stefenelli.
In the early 1900, having reconstructed the town 5 kilometers to the west of the former location of the settlement, the population was made up by 200 housing units. The railway station was raised at the venue that had been abandoned due to the flood. This station had different names throughout history: Río Negro, Los Perales and Padre Alejandro Stefenelli. However, this site was exclusively reserved for loading and unloading cars later on and the station was moved to its present location in 1931.
In 1912, this city that today has 100,000 denizens in 14,200 hectares of the urban grid, elected its first mayor: Mr. Alfredo Viterbori. The newspaper called Río Negro -in charge of Fernando Rajneri- was founded in those days. This paper still comes out and may be considered the most important throughout Patagonia.
The fruit growing industry began to develop little by little in General Roca until it spanned to three neighboring colonies. Likewise, culture played a significant role in Roca, starting with the foundation of the library called Biblioteca Popular Julio Argentino Roca in 1936, of the school known as Colegio Nacional de Enseñanza Secundaria in 1942, Lorenzo Vintter Regional Museum in 1949 and of course the creation of the House of Culture in 1972.