Costanera Sur Ecological Reserve

The Reserva Ecológica Costanera Sur exists by accident. In the 1970s a plan to extend the city into the river filled a stretch of the Plata with rubble from demolished buildings, then abandoned the project; water pooled behind the embankments, seeds arrived on the wind and in birds, and within a decade a wetland had formed on the ruins. Today it covers around 350 hectares of lagoons, reed beds, pampas grassland and willow woodland immediately beside the towers of Puerto Madero, with more than three hundred bird species recorded, along with coypu, lizards and the occasional river turtle. Wide gravel paths cross it, cyclists and joggers use it heavily at weekends, and viewpoints look out over the brown expanse of the Río de la Plata.

What you actually see

• The lagoons - open water and reed beds with herons, ducks and coots.
• The city contrast - Puerto Madero towers rising directly behind the wetland.
• The river shore - views over the Río de la Plata from the outer path.
• The wildlife - coypu, lizards and hundreds of bird species.

When to go

Year-round; spring and autumn bring migrants and comfortable temperatures. It closes on Mondays and after heavy rain when paths flood. Early morning is best for birds and cooler air, as there is little shade.

Honest expectations

Paths are wide gravel tracks shared with cyclists and runners, so it is a city park with wildlife rather than wilderness. Summer heat and mosquitoes are significant. The river itself is muddy brown and not for swimming.

Nearby

Puerto Madero and its docks adjoin the reserve; San Telmo lies a short walk west.