Every July, the folk- and arts-centric Greater New Bedford Summerfest (New Bedford Whaling National Historic Park, 508/979-1568, www.newbedfordsummerfest.com [1]) takes over the city with its whaleboat races, fireworks, performances, and plentiful seafood.
And during the first weekend in August, upwards of a hundred thousand pour into New Bedford [2] for the Portuguese Annual Feast of the Blessed Sacrament (at the junction of Achushnet Ave., and Earle St., 508/992-6911, www.portuguesefeast.com [3]). The massive celebration dates back to 1915 and is a frenzy of live entertainment, Portuguese foods, music, and dance.
Links:
[1] http://www.newbedfordsummerfest.com
[2] http://www.moon.com/destinations/new-england/massachusetts/eastern-massachusetts/south-boston/new-bedford
[3] http://www.portuguesefeast.com