Las Grutas - Rio Negro - Patagonia Argentina - Vista aerea San Antonio, Río Negro, Argentina Las Grutas is a beach resort town located in the Argentine province of Río Negro, in the department of San Antonio, with a stable population of 3,500 inhabitants.It's located 15 kilometers southern of San Antonio Oeste, and is visited by over 250,000 tourist every summer. Its beaches are known for having relatively warm waters in spite of their location in the Patagonia, due to the wide tidal amplitude, and the protection of the San Matías Gulf. The town was founded in 1964, mainly as a group of campings, and soon began growing. But it was not until the 1980s that tourism industry finally exploded, with the construction of numerous hotels and a provincial casino. Southern Right Whales are seasonal residents and visit here, and the Gulf of San Matias is the only water in the world where commercial swimming activities with this gentle giants are legalized.Las Grutas', meaning "The Caves" in Spanish, comes from the caves created by the erosion of the sea on the cliffs that separate the city from the beach. The access to the beaches is therefore restricted to the existing 12 descends or "bajadas". Their names, from north to south, are "3 de febrero", "Los acantilados", "A.C.A.", "La rueda", "Cero", "Primera", "Segunda", "Tercera", "Cuarta", "Quinta", "Sexta" y "Séptima", the last seven named from first to seventh.The first accesses where the ones named "Primera", "Segunda", and "Tercera" (first, second and third), to which new ones were added as the town, and the number of visitors grew.Near the "Cero" access there are pools artificially carved in the stone that change their water in every tidal cycle. When the tide is low, the water in the pools is quickly warmed by the sun. In colder days, old people and children sometimes prefer to make use of the pools instead of the sea.