The Sierra de la Ventana, also known as Sierras de Ventania, is a mountain range in Buenos Aires Province. The highest elevation is the Tres Picos at 1'239 m. As a special feature, there is a natural opening after which the entire mountain range is named: la ventana (the window), which is located (appr. 38° 2'55.14"S 62° 1'3.04"W),
Argentina 1977, Sierra de la Ventana.
The stamp was issued in the series " Views – Central Argentina".
Argentina 1984, the natural window of the Sierra de la Ventana.