A rally organizers have billed as the "largest secular event in world history" will be held on the National Mall today.
The Reason Rally will bring atheists and nonbelievers together in a hallowed American place.
But Paul Fidalgo of the Center for Inquiry, one of the organizations involved, says, "It's not a march on Washington where we're picketing anything. It's a celebration of the fact that the secular movement is really starting to come into its own."
Crowds of people dressed in white and waving yellow flags lined the highway outside the Leon airport in the central Mexican state of Guanajuato to welcome Pope Benedict XVI. They cheered wildly when the grinning, 84-year-old pontiff sped past in his glass-sided popemobile.
The pope began his weeklong trip to Latin America on Friday afternoon. He's spending the weekend in Mexico before heading to Cuba.
Protesters rally for religious freedom in front of Philadelphia's Independence Hall on Friday. Rallies took place nationwide to protest the mandate that some religious organizations cover the cost of contraception.
Across the country, thousands of people skipped lunch Friday to protest what they see as a threat to religious liberties in the United States.
The protesters' specific complaint was the birth control mandate in the new health care law, but the discontent runs far deeper.
It didn't take much for the Rev. Pat Mahoney, an evangelical minister, to warm up the crowd in Washington. He gazed out at hundreds of people who filled the plaza in front of Kathleen Sebelius' office at the Department of Health and Human Services.
Thousands of people are expect to descend on the Mall in Washington, D.C., on Saturday to celebrate not believing in God. It's being called a sort of "Woodstock for Atheists," a chance for atheists to show their power in numbers and change their image.
The "Reason Rally" could attract up to 30,000 people; organizer David Silverman says it marks a coming-of-age for nonbelievers.
"We'll look back at the Reason Rally as one of the game-changing events when people started to look at atheism and look at atheists in a different light," Silverman says.
Pope Benedict XVI is expected to speak out against drug violence during his visit to Mexico, which begins Friday. Here, an actor is shown in front of a poster announcing the pope's visit Wednesday in the Mexican city of Leon, Guanajuato state.
Pope Benedict XVI begins a visit Friday that takes him to Mexico, a country with around 100 million Catholics, and to Cuba, a place where church leaders have played an increasingly active role in seeking change.
There are sensitive issues in both countries that the pope is likely to address in some form. In Mexico, it's the brutal drug war that has claimed roughly 50,000 lives over the past five years.