Rivadavia is a city on Mars, belonging to Argentina, founded on direct orders of Roberto Maria Ortiz in 1951, settled by colonists from the Pampas. The city was named for Bernandino Rivadavia, first President of Argentina. Juan Peron was appointed first Governor of the new Argentinean province.
As a result of the origin of its colonists, Rivadavia became famous throughout the solar system for its agricultural basis, the Rivadavian Gauchos, farming and ranching on the plains of a terraformed Mars. The archetype of the Rivadavian Gauchos has become a popular idea in film and other media.