For Dayana Barros, Carnival always meant leaving Sao Paulo for the northeastern Brazilian city of Salvador, where she participated in its famous street parties throughout her childhood.

But in the past few years, Sao Paulo has experienced an explosion of "blocos," the singing and dancing parties normally associated with Carnival in Brazil's northeast and, more recently, Rio de Janeiro.

"Things started to be similar here," said Barros, a 28-year-old psychologist who is gearing up to celebrate the holiday in her hometown for the second year running.

This year, the metropolis that many have traditionally seen as too buttoned-up and serious to host a good party expects 4 million people to flood its streets — making the celebrations in Brazil's financial capital competitive with those in Salvador and Rio.

"The goal for everyone is to have the best Carnival the city has ever had and, who knows, the best in the country," city official Claudio Carvalho told reporters at a news conference trumpeting the recent growth of Sao Paulo's Carnival.

Mayor Joao Doria added that hotel occupancy for the holiday period is already nearly 70 percent — compared to an average of 25 percent a decade ago when Sao Paulo hotels considered the Carnival period to be a low season.

Then, the city was largely a ghost town as shops closed and revelers fled to more festive places across Brazil to celebrate the biggest party of the year.

"Street carnival was snuffed out for several decades," said Pedro Goncalves, who in 2013 co-founded Sao Paulo's "Bloco Bastardo," which focuses on traditional Carnival songs. "The tradition was to leave Sao Paulo."

While there were always a handful of blocos here, an increasing number started to appear around the beginning of this decade. The trend accelerated in 2014, when city hall began taking the parties out of a legal gray area by implementing regulations and offering official support, like closing streets and providing portable toilets.

That year, there were 200 street parties; this year there will be nearly 500.

"It is an explosion here, as if people had been held (back) for decades and now they want to take Sao Paulo streets back," said Elba Ramalho, a well-known singer from the northeastern city of Recife, who led a pre-Carnival street party in Sao Paulo for the first time Saturday.

The hundreds of large and small blocos planned across the city now include celebrations with themes as diverse as LGBT rights, Bantu culture and electronic music. Some invite parents to bring their babies along. Others promise DJs or more traditional parades with drums.

But Carnival is no mere party. Brazilians see it as an essential expression and reflection of their culture, and view the act of taking control of the streets as an important check on power in a country that has known dictatorship and still experiences high levels of inequality.

"It's a right," Goncalves said. Carnival "is linked to a sense of citizenship and community, of getting together with people near you and creating a culture."

Sao Paulo's reawakening is part of a larger trend of taking back urban spaces, such as the creation of bike lanes and pedestrian zones.

It also comes at a time of tremendous national upheaval.

In 2013, the country saw huge anti-government protests, which were the largest public demonstrations in Brazil in decades. In the years that followed, the country fell into one of the deepest recessions in its modern history, its first female president was impeached and removed from office, and the largest corruption investigation in Latin American history revealed unprecedented graft.

Marcos Maia, a historian of samba and Carnival, noted that many cities have seen their most exuberant street celebrations in the most politically or economically difficult moments, since Carnival can provide a kind of release.

In fact, many cite Carnival's connection with political unrest as a reason that street parties were initially wiped out in Sao Paulo.

As the city's Carnival celebrations began to grow in the first decades of the 20th century, authorities encouraged the formation of samba schools and progressively corralled the parades and competitions among them onto a handful of avenues as a way to control the festivities. The intolerance of spontaneous celebrations grew during the 1964-1985 dictatorship and was especially strict in Sao Paulo, which was a center of the anti-government union movement.

This year, some saw an echo of past efforts to control celebrations in the mayor's proposal to move several blocos from a main neighborhood of celebration to a drab avenue that runs through the city's heart. The blocos resisted, and they were allowed to remain.

Ze Cury, who is the director of the bloco "Me Lembra Que Eu Vou," or "Remind Me and I'll Go," said spontaneity and choosing where you parade are critical.

"Carnival belongs to whoever wants to do it in the street. Period," he said. "Carnival has no owner. Period."


Associated Press writer Mauricio Savarese contributed to this report.