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People hold signs as they gather to celebrate the 50th anniversary of the March on Washington.
People are assembling on the National Mall to commemorate the 50th anniversary of Martin Luther King Jr.'s 1963 March on Washington, best known as the venue for the iconic "I Have a Dream" speech that helped galvanize the civil rights movement.
Organizers, including the Rev. Al Sharpton and King's son, Martin Luther King III, say they expect 100,000 people to attend Saturday's events leading up the official Aug. 28 anniversary.
Speeches will be followed by a half-mile walk from the Lincoln Memorial to the 2-year-old Martin Luther King Jr. Memorial.
NPR's Allison Keyes, speaking with Weekend Edition Saturday host Scott Simon, says as of early Saturday there had been a steady stream of people gathering near the Lincoln Memorial.
"Groups of smiling black people, young people, old people — some who were at the  march," Keyes says. "I've seen a few whites and a few Latinos".
She says some people in their 20s and 30s "want to be part of history. They weren't born yet in 1963 when their parents marched," others are concerned about what they see as a "consistent turning back the clock on progress."
"They're talking about the Supreme Court decision that just struck down part of the Voting Rights Act, they are talking about Stand Your Ground laws, Stop-and-Frisk in New York City, there are a lot of people that say the verdict in the Trayvon Martin case has been a thing that upset them," Keyes says.
David Cakely from Goose Creek, S.C., who attended the march five decades ago, tells NPR that he's a little sad that some of the same issues talked about then have yet to be resolved.
"I was kind of disappointed on that," Cakely says. "I thought by this time we would have had all this taken care of – everybody moving together, Kumbaya, but that's not the case right now, so we're ... here today to show America that we're concerned."