Estancia San Alonso is a 10,700 hectare (26,600 acres) ranch located in the middle of the Esteros del Iberá. Historically, San Alonso had been managed as a large cattle operation up until 1996, when it was purchased by The Conservation Land Trust (CLT) for land conservation purposes. The uniqueness of it's location and it's relative isolation gives this ranch high conservation value and today it serves as one of the key areas for CLT's species reintroduction program that is ongoing in the Esteros del Iberá. The combination of eco-tourism and conservation in San Alonso allows visitors to see this private conservation area and get to know the flora and fauna of the esteros in a private atmosphere.
The main house of San Alonso sits at the shore of the Paraná Lake in the middle of the Esteros del Iberá and is coolly shaded by a grove of old lapacho and timbo trees. From there visitors can walk or ride out onto the savannah, through native forests, around waterways. There is also a boat which will take visitors out around the Parana Lake and up the well known Carambola River.