Relay for America runs flag from San Francisco to D.C. in message of unity: Relay for America ran the American flag from San Francisco to Washington, D.C., this week to commemorate America's 250th birthday. They did it nonstop for 20 days and nights for more than 3,000 miles on a mission of unity heading to the Fourth of July. Tony Dokoupil has the story. #RelayForAmerica #Unity #AmericanFlag #IndependenceDay #250YearsStrong