Continued from page 1

For tech-savvy revelers, Rio launched a smartphone app, free for iPhones and Androids, that tells visitors in English, Spanish or Portuguese where to go for blocos, the mobile samba bands that draw millions, pied-piper style, through the streets, as well as basic information on public transit, eateries and museums.

Brazil’s federal aviation authority expects 3 million people to shuttle in and out of airports during Carnival week, 13 percent more than last year. Airports taking in visitors will also have 30 percent more federal police, and workers with vests asking “May I help you?” will be circulating to take care of last-minute questions.

Helping the notoriously gridlocked city tackle the street closures, mass gatherings and parading parties is Rio’s new central command center, which the city hopes will keep order when Rio hosts the 2014 World Cup matches and the 2016 Olympics.

It has been fully operational since November, but this is the first big test of its ability to keep the city running during a large event.

The center takes feeds from more than 500 cameras spread around the city and will help plot the routes of Rio’s more than 400 roving street parties, along with the points were guards, medical units and toilets will be placed.

Center director Savio Franco said he hopes all this planning will make it a cinch to maintain control of Carnival.

“There will be more than 5,000 city government workers involved in making this party go as smoothly as possible for cariocas and for the tourists,” Franco said.