Buenos Aires was the capital city of Argentina. Rex Matheson and Esther Drummond went there to investigate the Miracle Day phenomenon.

They had already discovered that the Blessing was located through the Earth from Buenos Aires to Shanghai, its antipode. (TV: The Gathering)

Two maps of Buenos Aires were shown to the CIA; one by Noah Vickers as part of a planning process, and the other after Rex Matheson and Esther Drummond were thought to have died in a suicide bombing. The maps revealed the city's streets to include:

Buenos Aires map

The map that Noah presented. (TV: The Blood Line)

Buenos Aires map2

The second map seen by the CIA. (TV: The Blood Line)

(TV: The Blood Line)