Pope Francis, global leader of the Catholic Church, is scheduled to land Tuesday afternoon at a Maryland military base for his first U.S. visit — a six-day trip to Washington, New York City and Philadelphia. Events include a White House meeting with the president Wednesday morning, followed by a "Popemobile" parade along three streets in the capital and an outdoor mass that evening. Among other planned stops are a speech to Congress, a mass at Madison Square Garden in New York, a Harlem parochial school visit, a United Nations address and prayers at the National September 11 Memorial and Museum. He also may join a large environmental rally on the National Mall in Washington to reinforce his emphasis on protecting the planet.

The 78-year-old religious leader hasn't visited America before. This first visit is timed to let him speak at the World Meeting of Families in Philadelphia, a Vatican-sponsored event held every three years. It runs from Tuesday through Sunday. While in that city, the pope will visit a prison holding 2,800 inmates. At the facility's furniture shop, some lawbreakers made and upholstered a decorative special chair the famous visitor will use. "It's really going to bring a level of humanity to the prison world and show that prisoners are people and deserve to be recognized," a Pennsylvania advocacy group director says.

Francis was a cardinal from Argentina when fellow cardinals elected him in March 2013 at the Vatican (church headquarters in Italy). Here are vivid reminders that when we talk about Catholic popes, we’re talking about an epic sweep of history: This pope is the 266th man in that position, and the church’s first non-European leader in more than 1,200 years. By comparison, Barack Obama is just the 44th president of our relatively young country (239 years old). There are an estimated 1.2 billion Roman Catholics in the world, compared to 319 million Americans overall (including about 69.4 million Catholics).

N.Y. archbishop says: "He's a little nervous about coming. . . . He readily admits he has never been to the United States." – Timothy Dolan, head of the New York Archdiocese

Tight security: "He likes to get out with the people. And with that comes a large security risk. . . . We’re all very . . . vigilant to protect him." -- Congressman Mike McCaul, R-Texas, chairman of the House Homeland Security Committee

Earlier travels: The United States is the 15th country Francis has visited in more than two years as pope.