Carnaval in different parts of Brasil is as different as Brasil itself. Though some (not any guys that I've spoken to) may disagree, the common thread linking the Carnavals is booze and debauchery.
I spent my Carnaval in Rio, where the festival is all about Samba. The main event is the desfile (parade).
With a little help from photoshop:
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All places to stay are ridiculously pricey during the festival, but I went with Vanessa and we stayed with her brother (a Major in the army) on a military compound -that was kinda neat.
During the days we went to beaches -the main ones, as well as some private and open only to the military and their families. During the evenings we went out on the town.
One neat thing was seeing hang gliders land on the beach at São Conrado. Looks like good fun!
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There isn't much more to say about Carnaval. Check out my pics in the album. I do fear the wrath of my mother and, thus, photos of nudes have been mostly left out.