Atheists and other nonbelievers are gathering Saturday on the National Mall for what organizers say may be the largest secular gathering in Washington's history.
Thousands of atheists, humanists and others are expected to gather for the "Reason Rally," featuring speakers, music and comedy. Organizers say they also expect to be challenged by religious groups.
The National Park Service says a permit calls for an estimated crowd of 15,000.
The American Humanist Society is one of the primary sponsors. Roy Speckhardt, the group's executive director, says the rally will be a "coming out party" for humanists and atheists and a rally for political change.
Atheists held their first large gathering on the Mall in 2002. It was billed as "The Godless March on Washington."