The parades, a carefully timed competition, mark the climax of what all of Rio calls "the greatest show on Earth."
Twelve samba schools were to strut along a purpose-built, 70,000-seat Sambodrome stadium, under themes including environmental protection and homage to mermaids and other maritime mythology.
Brazilian President Luiz Inacio Lula da Silva was to attend Sunday night's parade -- the first time he has joined the Rio festivities since taking office in 2003.
All of Brazil has thrown itself into the partying with gusto, setting aside for the duration of the pre-Lent Carnival worris over the deepening impact of the global economic crisis, and chronic crime.
Foreigners were extra cautious in Rio despite the deployment of 9,800 police to boost security.
Nearly 100 had been victims of robbers, most of them armed gangs, in the lead-up to the festivities.
In two of the worst cases, gangs trussed up all the guests of two city hostels at gunpoint, stealing cash, iPods and cameras in pre-dawn raids from nearly 50 tourists.
New mayor Eduardo Paes tried to minimize the violence when he opened the partying on Friday, saying Rio was "the best city in the world to have fun during Carnival."
Crime is the biggest stumbling block to Rio de Janeiro's bid to win the 2016 Olympic Games.
Paes has thrown himself behind the campaign, which, if successful, would bring 14.4 billion dollars of improvements to the city -- and bring the Olympics to South America for the first time.
The head of the tourist police, Fernando Veloso, was confident.
"I think Rio will be prepared, very well prepared. One or two cases won't ruin Rio's image. There is always a problem of some sort. But every big city has problems," he told AFP.
Foreigners said they were aware of the risk, but they were not dissuaded from joining the partying.
"I think the most tourist zone is not so dangerous, and I don't go to the most dangerous zones," Thomas Spagnolatti, a 35-year-old Italian tourist sitting in a Copacabana beach cafe, said.
In Rio's many street parties, called "blocos," the emphasis was on sweaty, beer-fueled fun.
Tourists and locals danced as they filed behind trucks blaring foot-stomping rhythms, wearing little more than shorts and bikinis.
The exuberance was just as grand at exclusive fetes where fancy-dress and black-tie guests paid up to hundreds of dollars to get in.
At the most luxurious of them all, at the top Copacabana Palace Hotel on Saturday night, Brazilian models, TV stars, business tycoons and well-heeled foreigners danced to dawn in stylized debauchery.
The Brazilian government is doing all it can to temper the risks of Carnival's sexual fervor, handing out 59 million free condoms across the country.
When the partying is done, Brazil will come back to reality with a jolt.
The financial and economic crisis is leaving an increasing number of corporate casualties.
Embraer, Brazil's aircraft manufacturer, announced on Carnival's eve it was laying off more than 4,000 workers. Other big companies are poised to follow suit.
The consequences are likely to be worse than any hangover -- and maybe sobering enough to make many here think of this Carnival as the last carefree party for some time to come.
Twelve samba schools were to strut along a purpose-built, 70,000-seat Sambodrome stadium, under themes including environmental protection and homage to mermaids and other maritime mythology.
Brazilian President Luiz Inacio Lula da Silva was to attend Sunday night's parade -- the first time he has joined the Rio festivities since taking office in 2003.
All of Brazil has thrown itself into the partying with gusto, setting aside for the duration of the pre-Lent Carnival worris over the deepening impact of the global economic crisis, and chronic crime.
Foreigners were extra cautious in Rio despite the deployment of 9,800 police to boost security.
Nearly 100 had been victims of robbers, most of them armed gangs, in the lead-up to the festivities.
In two of the worst cases, gangs trussed up all the guests of two city hostels at gunpoint, stealing cash, iPods and cameras in pre-dawn raids from nearly 50 tourists.
New mayor Eduardo Paes tried to minimize the violence when he opened the partying on Friday, saying Rio was "the best city in the world to have fun during Carnival."
Crime is the biggest stumbling block to Rio de Janeiro's bid to win the 2016 Olympic Games.
Paes has thrown himself behind the campaign, which, if successful, would bring 14.4 billion dollars of improvements to the city -- and bring the Olympics to South America for the first time.
The head of the tourist police, Fernando Veloso, was confident.
"I think Rio will be prepared, very well prepared. One or two cases won't ruin Rio's image. There is always a problem of some sort. But every big city has problems," he told AFP.
Foreigners said they were aware of the risk, but they were not dissuaded from joining the partying.
"I think the most tourist zone is not so dangerous, and I don't go to the most dangerous zones," Thomas Spagnolatti, a 35-year-old Italian tourist sitting in a Copacabana beach cafe, said.
In Rio's many street parties, called "blocos," the emphasis was on sweaty, beer-fueled fun.
Tourists and locals danced as they filed behind trucks blaring foot-stomping rhythms, wearing little more than shorts and bikinis.
The exuberance was just as grand at exclusive fetes where fancy-dress and black-tie guests paid up to hundreds of dollars to get in.
At the most luxurious of them all, at the top Copacabana Palace Hotel on Saturday night, Brazilian models, TV stars, business tycoons and well-heeled foreigners danced to dawn in stylized debauchery.
The Brazilian government is doing all it can to temper the risks of Carnival's sexual fervor, handing out 59 million free condoms across the country.
When the partying is done, Brazil will come back to reality with a jolt.
The financial and economic crisis is leaving an increasing number of corporate casualties.
Embraer, Brazil's aircraft manufacturer, announced on Carnival's eve it was laying off more than 4,000 workers. Other big companies are poised to follow suit.
The consequences are likely to be worse than any hangover -- and maybe sobering enough to make many here think of this Carnival as the last carefree party for some time to come.