Pics source source2 Info from BlogTwiBrasil via SheevaC
Taxi Scene - when Edward and Bella first arrive in busy Rio.
"The street to be used for filming is blocked from 500m radius and there are security everywhere. There are roadblocks installed, it was even reported that even residents were evacuated. The location is secured."
Breaking Dawn Chapter 5 Isle Esme p76
"Instead we took a taxi through the dark, teeming, living streets of Rio. Unable to understand a word of Edward's Portuguese instructions to the driver, I guessed that we were off to find a hotel before the next leg of our journey. A sharp twinge of something very close to stage fright twisted in the pit of my stomach as I considered that. The taxi continued through the swarming crowds until they thinned somewhat, and we appeared to be nearing the extreme western edge of the city, heading into the ocean. We stopped at the docks."