The Costanera Sur Ecological Reserve, also called the Buenos Aires Ecological Reserve, is one of the largest urban reserves in Latin America. It is located in the neighborhood of Puerto Madero, in the city of Buenos Aires, Argentina.
It has two incomes, the main one is the South access (ex Brazil entrance) and the north access (ex Viamonte entrance). It is open from Tuesday to Sunday from 8 to 18 (winter time) and from 8 to 19 (in summer). Mondays and rainy days remain closed.

In its 350 ha. it houses more than 2000 species among birds, mammals, amphibians, reptiles and native vegetation, such as grassland grasslands and alder forests. In addition, it has viewpoints to the Río de la Plata. Due to its characteristics, it is suitable for hiking and bird watching.

The Reserve is part of an ecological corridor called Ecoruta del Río de la Plata, a circuit of more than 100 km in length that connects the green spaces and protected areas of the AMBA and surrounding areas. Among them, the Delta Biosphere Reserve of the Paraná River and the Ciervo de los Pantanos National Park stand out.

The Reserve is a center for bird watching, a Bird Observer Club belonging to Argentine Birds, founded on May 17, 2008. It was declared as an Area of ​​Importance for Bird Conservation, registering more of 300 species In it, 343 species of birds coexist, almost one third of all those in Argentina and 3% of the total birds in the world. You can see mistos, silver piquito, real carpenters, calenders and goldfinches, to name a few. In its lagoons you can also see aquatic species such as chajá, jacana, black-necked swans and common maca, as well as the sirirí pampa duck (protagonist of the Reserve logo).

In the 10 kilometers of trails you can perform different activities such as hiking. The Reserve has four suggested tours for visitors with different levels of difficulty and extension. The Circuit of the Wetlands stands out for its high biodiversity, the Circuit of the River, optimal for bird watching and reaching the viewpoints of the Rio de la Plata directly. The Circuit of Landscapes, meanwhile, transits the different ecosystems of the Reserve: the four types of wetlands, grassland grassland and chilca scrub. With 8 km of extortion, the Big Circuit is the largest in the Reserve.

The Reserve is surrounded by emblematic works and buildings. Here the Municipal Spa, symbol of the belle epoque of Buenos Aires, worked. It is still possible to know buildings of those times, such as the boulevard or the former Munich Brewery. Also noteworthy are the Fountain of the Nereids, by Lola Mora, located in the South access (former entrance Brazil). Other nearby points of interest are the Women’s Bridge, the Micaela Bastidas park or the Fortabat Museum.

The Ecological Reserve is open throughout the year, and is accessed free of charge, by its entrance located in what was the breakwater of the Costanera Sur (sector that has bathrooms and information center), or by the north entrance, without facilities, at the height of what would be the imaginary extension of Viamonte street on the coast.

Its address is Avenida Tristán Achával Rodríguez 1550