What was the capital of the union of provinces in the Río de la Plata comprised by most of the former dependencies from the last to be organized and also the shortest-lived of the Viceroyalties of the Spanish Empire in the Americas?
United Provinces of the Rio de la Plata The United Provinces of the Río de la Plata (Spanish: "Provincias Unidas del Río de la Plata" ), earlier known as the United Provinces of South America (Spanish: "Provincias Unidas de Sudamérica" ), a union of provinces in the Río de la Plata region of South America, emerged from the May Revolution in 1810 and the Argentine War of Independence of 1810–1818. It comprised most of the former Viceroyalty of the Río de la Plata dependencies and had Buenos Aires as its capital.
Punta Arenas Punta Arenas (or Sandy Point in English) is the capital city of Chile's southernmost region, Magallanes and Antartica Chilena. The city was officially renamed as Magallanes in 1927, but in 1938 it was changed back to "Punta Arenas". It is the largest city south of the 46th parallel south. As of 1977 Punta Arenas has been one of only two free ports in Chile. (Note that Punta Arenas itself is not a "free port", but rather outside of the city; there is a small "zona franca" where certain products can be imported into the country under a reduced-tax regimen.)