AP PHOTOS: The March on Washington

In a moment rich with history and symbolism, tens of thousands of Americans of all backgrounds and colors thronged to the National Mall Wednesday to join the nation's first black president and civil rights pioneers in marking the 50th anniversary of King's "I Have a Dream" speech.

At the National Cathedral in Washington, the central bell tower played "Lift Every Voice and Sing" from the carillon, along with other hymns and spirituals. The bells rang for about 15 minutes to mark the moment when the speech was delivered.

Here are some of the best photos from today.

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