This massive annual celebration takes place across an area of many blocks around Little Brazil in midtown Manhattan. It is held in late summer, and to get a sense of its frenetic, joyous energy, please see the video in my blog entry on the 2012 event.
At Brazilian Day you will encounter music, dancing, food, vendors with interesting wares (as well as the somewhat more mundane wares you see at street fairs generally), throngs of happy people, including families with kids, and a ton of green and yellow everywhere.