Rio de Janeiro's beach zones have the most reliable 4G LTE coverage. Copacabana beach front (Avenida Atlântica), Ipanema, Leblon, and Barra da Tijuca all have solid outdoor 4G. Claro and Vivo both have strong coverage along the beach corridors and major tourist strips. The Lapa arches area, Santa Teresa tram neighbourhood, and Centro historic district have usable 4G, with stronger signal on main roads than in narrow historic lanes.
Galeão International Airport (GIG) has 4G in both terminals. Santos Dumont Airport (SDU), the domestic city airport, also has 4G. The Riocard VLT tram system in Centro and the MetrôRio subway both have 4G at stations. The MetrôRio Line 1 and Line 4 underground sections have indoor station coverage but lose signal in the tunnels between stations.
Christ the Redeemer at Corcovado has 4G at the main viewing platform and the Cosme Velho station area. Signal can be intermittent at the statue itself due to the mountain location. Sugarloaf Mountain (Pão de Açúcar) has 4G at both cable car stations and at the summit platform, making photo sharing possible at the top. Tijuca National Forest, which runs through the city, has 4G at the main park entrances and picnic areas but weaker signal deep inside the forest.
Favela communities on hillsides have variable coverage. Santa Teresa and parts of Lapa have 4G. More remote hillside communities can have weaker signal. Barra da Tijuca, the modern beachside suburb to the west, has strong 4G and limited 5G. Niterói, across Guanabara Bay via ferry, has solid 4G from the same operators. New Zealand travellers should confirm their handset is unlocked and supports local network bands.