🇦🇷 Argentina · Buenos Aires
Ostende and Valeria del Mar are two adjoining seaside resorts in the Partido de Pinamar, on the Atlantic coast of Buenos Aires province, between Pinamar itself and the exclusive Cariló. They are wooded, quiet places, with tree-lined streets among pines, dunes and sea, built for a family holiday at rest, far from the noise of the big resorts. They form part of the forested belt that spreads over the old dunes stabilised with pines through the 20th century.
Ostende is the older of the two: it was born in the early 20th century as a Belgian-inspired resort project and keeps, as its great emblem, the old Hotel Ostende (Viejo Hotel Ostende), where Antoine de Saint-Exupéry stayed. Valeria del Mar, founded a little later, offers wide beaches, a residential family atmosphere and a smaller promenade. Both share the look of forest over sand, with dirt and paved streets running through pine woods.
In this guide you will find what to do in Valeria del Mar and Ostende, how much a beach tent costs in the 2026 season, how to get there from Buenos Aires by car or coach, where to sleep and eat on any budget, and how to combine your stay with Pinamar and Cariló, both minutes away. It is the calm corner of the Pinamar tourist hub, ideal for beach, forest and family rest.
Ostende was founded in 1908 by the Belgian Fernand Robette and the Italian Agustín Poli, who dreamed of reproducing the Belgian resort of the same name: the First World War sank the project and the sand buried its promenade. The Gran Hotel survived (today the Viejo Hotel Ostende), which hosted Saint-Exupéry and where Bioy Casares and Silvina Ocampo wrote 'Los que aman, odian' in 1946. Valeria del Mar was born in 1947, founded by Valeria Guerrero Cárdenas de Russo on forested dunes.
Read the full history ↓The agro-export heart of Argentina: the endless pampa that was the land of the Querandí and the Pampa peoples, the domain of governor Rosas, the engine of cattle and wheat with La Plata as its purpose-built capital, cradle of the gaucho and of the Atlantic Coast where the whole country spends its summer.
Read the history of Buenos Aires Province →No exact prices: a scale from $ (budget) to $$$$$ (luxury), with 2-3 options per category.
Origins, formation and what the sources say.
By around 1931, guests at the Gran Hotel in Ostende entered the building through a first-floor window, walking over planks laid on the sand. It was not an eccentricity: the live dunes of the Buenos Aires coast, pushed by southeasterly gales, had buried the hotel's ground floor, the promenade with its columns and balustrades, and several whole buildings of the resort. Ostende, the ambitious tourist project a group of Europeans had founded two decades earlier to reproduce Belgium's most elegant resort in Argentina, was being literally devoured by the sand desert it had dared to build on.
That image — a ghost hotel half-sunk among the dunes — is the key to the whole history of this corner of the Atlantic coast. Ostende and Valeria del Mar, today two placid, wooded resorts between Pinamar and Cariló, were born out of a century-long struggle between human ambition and the dunes. First the humans lost, spectacularly. Then, by planting millions of pines, they won. And in between, that hotel stranded in the sand became a refuge for legendary aviators and brilliant writers, and even the setting of one of the best Argentine crime novels.
At the start of the 20th century, the coastal strip between Cabo San Antonio and Mar del Plata was a desert of shifting dunes, with no trees, no roads and almost no inhabitants. The Belgian Fernand Robette and the Italian Agustín Poli set their sights on it, two entrepreneurs convinced that those untouched beaches could host a European-standard resort. In 1908 they founded Ostende — named after the famous Belgian resort on the North Sea — and the following year a Belgian company run by Robette bought 14 square kilometers of dunes to develop the project.
The plans were grand: avenues named after seaside cities around the world (Biarritz, El Cairo, Niza), a seafront promenade with columns and balustrade, chalets, services and a grand hotel. In 1913 construction began on the flagship building, the Hotel Termas — the future Gran Hotel Ostende — with more than 80 rooms facing the sea. For a moment the dream seemed to be coming true: the more adventurous Buenos Aires families took the train to the area and reached the brand-new resort by carriage along the beach.
The First World War changed everything. In 1914 Belgian capital was trapped in a Europe in flames, Robette returned home and the flow of investment stopped dead. Ostende was left orphaned halfway through, and the sand — which had never stopped moving — began its slow reconquest: it buried the promenade, covered whole streets and climbed the hotel walls until it blocked the ground floor completely by about 1931. The Belgian resort became a half-ghost town, with a handful of residents holding out among the dunes.
Paradoxically, it was that romantic decline that gave Ostende its place in Argentine cultural history. In the late 1920s, while running the operations of Aeroposta Argentina — the local arm of the legendary French Aéropostale that carried mail to Patagonia — the aviator and writer Antoine de Saint-Exupéry spent two consecutive summers staying at the Ostende hotel. The future author of 'The Little Prince' (1943) found in that building stranded among the dunes the solitude and silence he was looking for; his first-floor room is preserved to this day and is one of the hotel's great draws.
The second literary chapter is even better. In early 1946, Adolfo Bioy Casares and Silvina Ocampo — the most brilliant couple in Argentine literature, close friends of Borges — moved into the hotel at the end of summer and stayed until winter. Out of that long stay by the sea came 'Los que aman, odian', the only novel they wrote together: a crime story set in an isolated hotel among wind-lashed dunes, a transparent portrait of Ostende itself, considered a classic forerunner of Argentine noir and adapted for the screen in 2017.
Thanks to those illustrious guests, the 'Viejo Hotel Ostende' — as it was renamed — stopped being a melancholy ruin and became living heritage: a period hotel that still operates, where you can sleep in the same rooms that inspired Saint-Exupéry, Bioy and Silvina.
While Ostende slept under the sand, the decisive battle against the dunes was being fought on the neighboring land. The lesson of the Belgian failure was clear: before you build, you have to fix the dunes, and the only way to do that was to plant. In the 1930s and 1940s, two figures led that green crusade. To the north, the architect Jorge Bunge was developing Pinamar (founded in 1943), planting the dunes with maritime pines, acacias and wattles. And on the land in between, a woman took up the task: Valeria Guerrero Cárdenas de Russo, heir to the Guerrero family estancias, who arrived in 1938 determined to transform her share of coastal desert.
In 1941, Mrs de Russo joined forces with Bunge to take on the mass planting of trees on her dunes. They were years of work with spade and watering can: every pine had to be defended from wind, salt and drought until the roots took hold and the sand, at last, stayed still. Millions of trees later, the desert that had defeated the Belgians had become a continuous forest beside the sea: the famous forest belt that today links Montecarlo, Pinamar, Ostende, Valeria del Mar and Cariló, and which gives the whole district its identity.
That colossal work — an entire forest created by human hands in less than a generation — is the real founding of these resorts. Without the pines there would be no streets, no houses, no tourism: only sand on the move.
With the dunes finally tamed, Valeria Guerrero Cárdenas de Russo decided to found her own resort on the forested land she still held along the shore, between Ostende and the emerging Cariló. On 28 August 1947 the deed considered the birth certificate of Valeria del Mar was signed. For the name, the founder did not choose her own, as is often believed, but that of her grandmother, Valeria Cueto de Cárdenas: a family tribute that stuck to the sea for good.
The new resort grew with a character deliberately different from its neighbors': neither the commercial bustle of Pinamar nor the closed exclusivity of Cariló, but a residential town of houses among pines, quiet streets and wide beaches, built for families. That character held through the decades, while the group of resorts gained an identity of its own: in 1978 the Partido de Pinamar was created, split off from General Madariaga, bringing Pinamar, Ostende, Valeria del Mar and Cariló together administratively.
Ostende, for its part, slowly emerged from its slumber: the old Belgian street grid filled up again, the street names — Biarritz, El Cairo, Niza — went on recalling the original dream, and the Viejo Hotel established itself as a living monument to the first era. The two resorts, born of such different stories, ended up merged into a single fabric of forest and beach.
Today Ostende and Valeria del Mar are the quiet heart of the Pinamar district, one of the most sought-after tourist hubs on the Argentine Atlantic coast. Every summer they take in thousands of families who choose exactly what these resorts learned to build: wide beaches of pale sand, a pine forest reaching almost to the dunes, and a human scale of low houses and tree-lined streets, ten minutes from Pinamar's Avenida Bunge and Cariló's shopping strip.
History keeps showing through the pines. The Viejo Hotel Ostende — restored and running — lets you sleep among memorabilia of Saint-Exupéry and of Bioy and Silvina; the live dunes that once swallowed a whole resort are now the setting for 4x4 crossings and sandboarding; and the forest planted by hand in the 1940s is the open-air gym of cyclists, runners and riders. In a country where the coast usually means crowds, this corner of the Atlantic keeps something of the spirit of its dreamer founders: the idea that between sea and sand you can build a small paradise, as long as you have patience with the wind.