Huge gangs of young thieves swoop onto a beach rushing through the crowd stealing bags and ripping jewellery from bather's necks. The experience is frightening and usually causes a panic among beach-goers as they try to escape the drag net.
The arrastoes (Portugese for big drag) used to be common some years back, but diappeared when conditions in the favelas (slums) were improved. Here's amateur video of one happening on Ipanema beach in 2015. Scores of people were robbed and there was a panic.
Copacabana is the most renowned, but the local favourites Ipanema and Leblon are growing in popularity among tourists. The water isn‘t particularly clean, especially around the channel at Leblon.
Although Brazilians are comfortable with bikinis crafted from dental floss, topless sunbathing is not allowed.
The crowds mean a lot of petty crime goes unnoticed, so keep a watchful eye on your valuables. If you want to cool off in the water, and you‘re in a group, have someone stay and watch your valuables. Otherwise you can ask someone nearby to keep an eye on them, the Cariocas (Rio‘s residents) hate crime as much as you and will be happy to oblige.
The beaches are best avoided at night, with wandering tourists a target for robberies. If you do head down there beware of locals offering you drugs. They are usually working in concert with a nearby cop to extort a bribe from you.
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