Every summer the Smithsonian Institution puts on a folklife festival highlighting different peoples and communities from North America and around the world. There's food, dancing, crafts, music- all kinds of good stuff on the downtown mall in DC. This year one of the highlights is the Himalayan state of Bhutan. There will be a number of displays and demonstrations ranging from archery to architecture to textiles. If you're in the DC area it's definitely worth stopping by- much cheaper and quicker than a trip to Bhutan. The festival runs June 25-29 and July 2-6 from 11-5:30 with some evening events at 6.
If you need to beat the heat, check out the Freer and Sackler galleries on the south side of the mall near the arts and industries building. These galleries are home to a number of great Asian art and artifact exhibits from many different periods and dynasties of east, central, and south Asia.
Finally, if you've missed the folklife festival you can always go to the National Museum of the American Indian to see beautiful craftwork and artifacts. It is also one of the best places downtown to have lunch, offering native dishes from across North America.
