🇦🇷 Argentina · The Northeast and Mesopotamia
Concordia is the second city of Entre Ríos, on the Uruguay River, in the northeast of the province, and one of the great thermal destinations of the Argentine northeast. It combines hot springs famous across the country, the enormous lake of the binational Salto Grande dam, beaches on the river, a rich citrus-growing tradition and an unexpected literary treasure: San Carlos Castle, linked to Antoine de Saint-Exupéry and to The Little Prince.
Its thermal complexes are the great magnet: mineral-medicinal waters that rise from more than a thousand meters down, at warm temperatures, spread across parks with pools, water parks and services built for downtime and for families. Added to that is Salto Grande Lake, an immense sheet of water ideal for boating, fishing and sports, formed by the big hydroelectric dam that Argentina shares with Uruguay.
But perhaps the most magical part of Concordia is in San Carlos Park: there, among its 'ruins', stands San Carlos Castle, a 19th-century French-style mansion where —as the story goes— the aviator and writer Antoine de Saint-Exupéry lived through an episode that inspired part of The Little Prince. Hot springs, lake, river and literature: Concordia is a destination with many layers to uncover.
Concordia grew on the banks of the Uruguay River as a port, trading and citrus-growing city, and became the second city of Entre Ríos. In the 20th century, the construction of the binational Salto Grande dam (between Argentina and Uruguay) and, later, the development of the hot springs shaped its present profile. Its history also includes a celebrated literary chapter: the passage of the aviator Antoine de Saint-Exupéry through San Carlos Castle, in 1929, linked to the inspiration for The Little Prince. The full story is on our history page.
Read the full history ↓The Mesopotamian province between the Paraná and the Uruguay: land of Charrúas and Minuanes, stronghold of the federalism of Urquiza —the victor of Caseros—, cradle of Argentina's Jewish and Swiss colonies, of hot springs, palm groves and the carnival of Gualeguaychú.
Read the history of Entre Ríos →No exact prices: a scale from $ (budget) to $$$$$ (luxury), with 2-3 options per category.
Origins, formation and what the sources say.
One Sunday in October 1891, the French family living in the brand-new San Carlos Castle —a mansion shipped over from Europe, with English iron, Italian marble and French glass— made a sudden decision: pack their bags and move out, without giving any explanation. They never came back. They had lived there barely three years. The mansion, finished in 1888 on the highest rise of a park beside the Uruguay River, was left abandoned, and that abandonment was the first step toward the 'romantic ruins' that thousands of tourists visit today and toward the legend that, decades later, would cross paths with a French aviator named Antoine de Saint-Exupéry. That mix of opulence, mystery and literature is still today the best summary of Concordia's character.
But before that almost novelistic chapter, Concordia already had its own history as a border and river city. Founded by decree of the Provincial Congress on 29 November 1831 —put into effect the following year—, the city grew on the banks of the Uruguay River, in the northeast of Entre Ríos, as a crossing and trading point with neighboring Salto (in what is now the Eastern Republic of Uruguay). That border and riverside position made it, early on, a center of economic activity and the second most important city in the province, behind the capital, Paraná. In the heat of that prosperity came waves of Spanish, Italian and, especially, French immigrants, who founded their own Sociedad Francesa de Socorros Mutuos and left a cultural mark that can still be traced in the city, starting with San Carlos Castle itself.
One of the features that most shaped Concordia's identity is citrus growing. The region became one of Argentina's great orange and mandarin capitals, with vast citrus groves that perfumed its economy and its landscape for generations, and that today have their own popular festival. That citrus tradition is still in the air in the city, in its preserves, its juices and its productive culture, and it lives alongside its other great modern engine: thermal tourism.
The most celebrated chapter in Concordia's history has to do with literature and aviation, but it begins with the money and the extravagance of a family of Parisian bankers. On the riverbank, in what is now San Carlos Park, stands San Carlos Castle, a French-style mansion commissioned by Charles Édouard Demachy, a member of a family tied to the European financial system (the Demachy-Seillière firm), who had come to the region to take charge of industrial ventures backed by French capital. The mansion, with plans drawn up in Paris, was inaugurated in 1888 on the highest rise of the park, and was built almost entirely from materials imported from Europe: English iron, German wood, Italian marble and French glass; the only truly local material was the washed stone from the Uruguay River itself, used for the exterior cladding. But the family lived there only three years: one Sunday in October 1891 they decided to move out from one day to the next, leaving no explanation, and never returned. With no owners, no use and no maintenance, the property fell into decay until it became the romantic 'ruins' visited today.
Almost forty years after that departure, in December 1929, the French aviator Antoine de Saint-Exupéry, who was flying the airmail between Buenos Aires and Asunción for the company Aeroposta Argentina, had to make an emergency landing in his Latécoère 25 in a field near Concordia, next to the castle. He was received there by the Fuchs family, of French origin, who were living in the property at the time, and he lived through an experience he later evoked, moved, in his book Tierra de hombres: he wrote that he had landed in a field without knowing he was about to live through 'a fairy tale'. In that house he met the couple's daughters, Susana and Edda Fuchs, two girls who tamed wild animals and kept unusual species as pets —a fox, an iguana, a monkey, snakes—, a world that many connect with images and characters from his most famous work, The Little Prince (where the fox has a central role).
The building's final fate came shortly afterward: on 25 September 1938, a great fire whose causes were never established left it completely in ruins, and for some 75 years the old house stood abandoned and was looted, losing everything of value it held. Only in 2013 did the municipality complete the restoration works that now allow you to walk the ruins safely, with walkways, stairs and an interpretation center that tells the story of the Demachys, of the Fuchs family and of the aviator who made Concordia part of the legend of The Little Prince.
The idea of harnessing the power of the Uruguay River to generate energy was not born in the 20th century: the first application for a concession to produce electricity in the Salto Grande area was filed in 1890 by the Argentine engineer Gregorio T. Soler. But the project took more than eighty years to come about. It was only on 7 April 1961 that Argentina and Uruguay signed the Treaty of Boundaries on the Uruguay River, which laid the legal groundwork for the project, and construction formally began on 1 April 1974, with more than 4,500 workers on site at the same time at peak moments and a colossal use of materials: some 60,000 tonnes of iron and 1,500,000 cubic meters of concrete.
The first turbine came into service on 21 June 1979, and the fourteenth and last was inaugurated on 27 March 1983, completing the first binational hydroelectric plant in all of Latin America. The central concrete dam is 852 meters long, flanked by two earth dams —786 meters on the Uruguayan side and 849 meters on the Argentine side— and a spillway of 361 meters able to discharge up to 60,000 cubic meters of water per second. Its power supplies, in round figures, half of the Uruguayan electricity system and 5% of the Argentine one, and since 25 August 1982 its crest has also worked as a road and rail border crossing between Concordia and Salto, in Uruguay.
Beyond its energy and diplomatic role, the dam completely changed the region's landscape: by damming the Uruguay River it formed the enormous Salto Grande Lake, a sheet of water of hundreds of square kilometers that became a tourist attraction in its own right, ideal for boating, fishing and water sports. Today the dam can be visited to see how it works, and the lake is one of Concordia's great postcards.
Contemporary Concordia is, above all, a thermal city. From the late 20th century, the discovery and exploitation of mineral-medicinal waters —which rise hot from more than a thousand meters down— gave rise to several thermal complexes in the city and its surroundings, many of them near the dam and Salto Grande Lake. Those hot springs made it one of the great downtime destinations of the northeast, especially in autumn and winter.
To that thermal draw, Concordia adds its lake, its beaches on the Uruguay River, its citrus tradition and, as a cultural jewel, San Carlos Castle with its legend of Saint-Exupéry and The Little Prince. The city also works as a base for visiting El Palmar National Park and for crossing to Salto, in Uruguay, with its own thermal hub. River, energy, orange groves, healing waters and a literary fairy tale: few cities in the northeast bring together so many stories in one place.