The city associated with the world's largest New Year's Eve fireworks display over Copacabana Beach is Rio de Janeiro.
Rio's Reveillon celebration centers on Copacabana, a broad beach in the city's South Zone. Fireworks are launched from boats offshore, allowing the display to spread across the ocean-facing horizon while enormous crowds gather along the sand and the Avenida Atlântica waterfront.
The event combines fireworks with concerts, religious offerings, white clothing, and beach parties. Many participants wear white as a symbol of peace and renewal, while some honor Afro-Brazilian traditions by making offerings to Iemanjá, the sea-associated orixá.
Descriptions of the display as the “world's largest” can vary because crowd and fireworks records use different definitions. The stable fact is that Rio de Janeiro's Copacabana Reveillon is one of the world's largest and most internationally recognized New Year's Eve celebrations.