Bahía Blanca (Spanish pronunciation: [baˈi.a ˈβlaŋka]; English: White Bay) is a city in the southwest of the province of Buenos Aires, Argentina, by the Atlantic Ocean, and is the seat of government of the Bahía Blanca Partido. It had 301,572 inhabitants according to the 2010 census [INDEC]. It is the principal city in the Greater Bahía Blanca urban agglomeration.
The city has an important seaport with a depth of 45 feet (15 m), kept constant upstream almost all along the length of the bay, where the Napostá Stream drains.
Bahía Blanca means "White Bay". The name is due to the typical color of the salt covering the soil surrounding the shores. The bay (which is an estuary) was seen by Ferdinand Magellan during his first circumnavigation of the world on the order of Charles I of Spain in 1520, looking for a canal connecting the Atlantic to the Pacific Ocean along the coasts of South America.