The Rio Carnival happens once a year and it's a massive party in Rio de Janeiro, Brazil. The mayor opens the festival with an enormous key.
Loads of the carnival-goers dress up in fancy dress.
The first Rio Carnival was way back in 1723, and in modern times the floats are legendary.
One of the most important parts of the carnival is dancing. People dance on floats, through the streets and into the early hours of the morning, wearing spectacular costumes.
The main carnival takes place in the Sambadrome, but there are loads of street festivals throughout the city.
Music keeps the carnival going throughout the weekend, and keeps the dancers dancing.
The streets get packed with people wanting to experience one of the biggest parties in the world.
The purpose of carnival is for samba schools to compete with fellow rival schools, and there is a competition at the end of the whole festival. Samba is a type of Latin American dancing.
Madonna turned up to party with her daughter, Lourdes.
Bruna Bruno who's part of the Uniao da Ilha samba school, dances during carnival parade at the Sambadrome.
The Galo da Madrugada is considered to be the biggest street band in the world, with more than two million followers.
With the combination of the parade, the balls, and the street carnivals, Rio's carnival is often called the greatest show on Earth.