Rio de Janeiro is a city.
This is a list of the 33 administrative regions ( in região administrativa ) in the city of Rio de Janeiro , Brazil . Rio de Janeiro ( [ ˈriːoʊ_di_ʒəˈnɛəroʊ , _ - deɪ_ʒə - , _ - də_dʒə - ] [ ˈʁi.u d ( ʒi ) ʒɐˈnejɾu ] ; River of January ) , or simply Rio , is the second-most populous municipality in Brazil and the sixth-most populous in the Americas . Rio de Janeiro was the host of the 2016 Summer Olympics and the 2016 Summer Paralympics , making the city the first South American and Portuguese-speaking city to host the events , and the third time the Olympics were held in a Southern Hemisphere city .