The story of how this land changed hands is older and harder than the fort. Spanish expeditions led by Francisco de Villagra rode in from what is now Chile in 1551 and found the region already settled by agricultural peoples, the Coquimbo and the Diaguita, whose farms and irrigation predated the newcomers by generations. The colonists subdued them and seized the land. The displaced Pehuenche fought back across decades of raids until the 1804 treaty signed by Viceroy Rafael de Sobremonte formalized the loss, ceding territory to colonial authority. The fort that rose the following year was both a marker of that conquest and the seed of the city, a hard origin that San Rafael shares with much of the Americas.

For a long time San Rafael was simply too remote to matter, isolated from the rest of Argentina even after independence in 1816. What changed everything was water, and the will to manage it. In 1871 the civil engineer Julio Balloffet was sent to develop the town, and he built it the bones of a real city: schools, plazas, a hospital, a cathedral, and above all the irrigation canals that turned dry plain into productive orchard. By 1900 those fruit groves had drawn waves of Italian and French immigrants, whose labor and tastes still flavor the region's wine and food. Formal designation as department seat came in 1903, the railway arrived that November, and in 1922 San Rafael was officially a city. A frontier post had become a hub.

The same rivers that watered the orchards could also be made to generate power. The Atuel and the Diamante run torrential out of the mountains, and over the twentieth century engineers dammed them for hydroelectricity, reshaping the landscape in the process. The first major work, the Nihuiles hydroelectric system, entered service in 1957 on the Atuel and produces a striking share of the nation's power; it also created a reservoir of some 9,000 hectares that opened a whole new economy of lakeside recreation. The Los Reyunos dam followed on the Diamante in 1984. Around these waters grew the tourism that now defines southern Mendoza: rafting, sailing, and the dramatic painted gorge of the Cañón del Atuel just to the south.

Modern San Rafael wears its prosperity comfortably. It sits about 236 kilometres south of the provincial capital and a long 990 kilometres from Buenos Aires, far enough to keep its own unhurried character. The climate is cold and semi-arid, the kind of high-desert air that suits both vineyards and clear nights. Wine and fruit remain the economic backbone, but the city has a faster side too: since 1968 it has hosted motor racing at its autodrome, including rounds of Argentina's prized TC 2000 touring car series. Plazas shaded by trees, a cathedral at the center, rivers and reservoirs at the edges of town, and the white wall of the Andes on the western horizon: San Rafael has become exactly the kind of place its founders, staring out from a lonely fort, could never have imagined.