WASHINGTON -- Former Atlanta Mayor Andrew Young led off a 50th anniversary celebration of the March on Washington today on a musical note, and with a warning that 1963's quest for justice is not done.

"We're not here to claim any victory," the former U.S. Ambassador to the United Nations said. "We're just here to say the struggle continues."

From the same Lincoln Memorial steps where Dr. Martin Luther King Jr. delivered the "I Have a Dream" speech, Young led the crowd in a few bars of civil rights movement songs "Woke up this morning with my mind stayed on freedom" and "I've got a feeling everything's gonna be all right."

President Barack Obama is scheduled to join a string of Georgia politicians and civil rights figures speaking today, fitting for Atlanta and the state's prominent place in the civil rights movement.