Mary-Kate and Ashley Olsen celebrated their 29th birthday over the weekend and did so in a very patriotic style. The twins were front and center at an Olympics-themed bash in the Hamptons on Saturday, with their many friends posting photos to Instagram with the hashtag #OlsenOlympics. The party was full of games, including dunk tanks, fireworks, and obstacle courses, and guests sported t-shirts that said "Team Ashley" or "Team Mary-Kate." Judging by one photo from real estate broker Jared Seligman, Ashley's team came out victorious; he captioned this snap, "Champions #teamashley #olsenolympics #twinning #sorrymk." The girls' big party comes just a week after they took home the CFDA Award for womenswear designer of the year for their work on The Row. Keep reading to see photos from Mary-Kate and Ashley's Olympics party.