The National Mall in Washington, DC plays host to the Smithsonian Folklife Festival every summer. It is a huge, kid-friendly celebration of world cultures.
This free event is part of the Smithsonian Year of Music, an Institution-wide initiative celebrating the Smithsonian’s vast musical collections. It will take place on June 29-30 and plenty of delicious international cuisine will be available as well as activities for kids and musical performances.
Parking is very limited, so the best way to get there is on public transportation. More information is here