From the airport

 Rio’s airport is the Aeroporto Galeao (GIG) and is located on Ilha do Governador, 15km north of the city centre.  Real Auto Bus (0800 240 850) operates from the international airport, either outside the arrivals floor of Terminal 1 or the ground floor of Terminal 2. All buses are safe and air-conditioned and have routes to Rodoviaria Novo Rio, Av Rio Branco (Centro), Aeroporto Santos Dumont, southward of Gloria, Flamengo and Botafogo and along the beaches of Copacabana, Ipanema and Leblon to Barra da Tijuca (and all vice versa).
 Buses run every 30minutes, from 5:20am to 12:10am and will stop wherever you ask. Fares start from around US$2. If you are heading back to the airport then the Real Auto Bus service from in front of the major hotels and along the major beaches but you have to look aware and flag them down hard.

 Taxis from the airport may try to rip you off but if you get a radio taxi then a set fare can be better but possibly at a more expensive rate.