Pope Francis in NYC: Pontiff heads to UN, Ground Zero (PHOTOS, VIDEOS)

Pope Francis’ only full day in New York is packed with activities, starting with a speech to the United Nations General Assembly, followed by a visit to the National September 11 Memorial. New York City is the second stop of his historic visit to the US.

The pontiff took to the pulpit on the world stage Friday morning with a formal address to the UNGA. The 193-member international organization is celebrating the 70th anniversary of its founding in 2015. Francis is the fourth pope to speak to the general assembly.

Pope Francis signs a guest book at the United Nations as UN Secretary Ban Ki-moon looks on © Joshua Lott © Reuters

Before addressing world leaders, he talked to about 400 UN staffers in the Secretariat lobby, thanking them for making “possible many of the diplomatic, cultural, economic and political initiatives” of the United Nations.

Pope Francis laid a wreath at a memorial to UN staff who have lost their lives around the world while doing their jobs.

Pope Francis pays tribute to those who have died in service to the United Nations around the world as UN Secretary General Ban Ki-moon looks on © Tony Gentile © Reuters

He also blessed the children in attendance.

During his speech to the UNGA, Pope Francis took on many hot-button international issues, calling on the world to quickly address climate change and help the least fortunate members of society.

“Economic and social exclusion is a complete denial of human fraternity and a grave offense against human rights and the environment,” Francis said, adding that “the poorest are those who suffer most from such offenses” because “they are cast off by society, forced to live off what is discarded and suffer unjustly from the abuse of the environment.”

READ MORE: 10 controversies swirling around Pope Francis’ visit to the US

“Any harm done to the environment,” he said, “is harm done to humanity.”

He also called on the UNGA to address the humanitarian crisis overtaking Europe as migrants and refugees flood out of the Middle East.

Pope Francis then left the United Nations and headed to the World Trade Center complex, where he was joined by some 1,000 members of the 9/11 community at the National September 11 Memorial & Museum.

After a moment of silence in front of one of the twin memorial pools, which sits within the footprint left by the southern Twin Tower, the pope laid a white rose on the bronze panel surrounding the fountain. The names of every person who died in the 2001 and 1993 terrorist attacks on the World Trade Center are inscribed on the panel.

Once inside the National September 11 Museum, the pontiff met with local representatives of the world religions and held an interfaith meeting for peace.

"The name of so many loved ones are written around the towers' footprints. We can see them, we can touch them, and we can never forget them," Francis said in his address, which he gave in Spanish, during the service. "This place of death became a place of life too, a place of saved lives, a hymn to the triumph of life over the prophets of destruction and death, to goodness over evil, to reconciliation and unity over hatred and division."

Rabbi Elliot Cosgrove of the Park Avenue Synagogue in Manhattan and Imam Khalid Latif, executive director and chaplain of the Islamic Center at New York University, also spoke during the meeting.

Rabbi Elliot Cosgrove and Imam Khalid Latif shake hands in front of Pope Francis during an interfaith ceremony at the 9/11 Memorial Museum © Tony Gentile © Reuters

Pope Francis then met with relatives of those who died in the 9/11 terrorist attacks. Former New York Mayor Michael Bloomberg, the chairman of the National September 11 Memorial & Museum, introduced the family members to the pontiff.

Former NYC Mayor Michael Bloomberg and Cardinal Timothy Dolan escort Pope Francis through the 9/11 Memorial & Museum © Susan Watts © Reuters

Thursday afternoon, the pope visited Our Lady Queen of Angels, a 120-year-old Catholic elementary school in the East Harlem neighborhood of Manhattan. The student body is 70 percent Hispanic and 22 percent African American.

Hundreds of students and educators from other Catholic elementary and high schools in Manhattan greeted Pope Francis outside the school.

Pope Francis visits Our Lady Queen of Angels School in East Harlem ©  Eric Thayer/New York Times/POOL

They presented the pope with a "spiritual bouquet" collection of prayers, photographs and drawings by the students bound in a hardcover book.

Inside, about two dozen Our Lady Queen of Angels third- and fourth-graders met, spoke and prayed with Pope Francis.

They showed the pontiff school projects and ongoing lessons “focusing on stewardship of the environment and community service," organizers said.

Leaving Harlem and heading downtown, Francis eschewed the traditional carriage ride in Central Park for a papal procession through the 843-acre green space while riding in his custom Jeep Wrangler, the “Popemobile.”

Pope Francis rides in a motorcade in New York's Central Park © Reuters / Richard Drew/AP/POOL

New York held a lottery to dole out 80,000 tickets for residents to attend the parade.

Gates opened at 11 a.m. and people were supposed to be inside the park by 3:30 p.m. However, crowds were still flowing through the security gates well after. Police told Newsweek they would stop letting people in “when they feel like it.”

Meanwhile downtown, people slowly began to fill into the iconic Madison Square Garden arena, where the pope is set to celebrate Mass. Attendees were treated to a pre-service concert.

Singer Gloria Estefan performed ‘Mas Allá,’ the same song she sang for Pope John Paul II. Jennifer Hudson and Harry Connick Jr. also served as opening acts for the pontiff.

Priests heard confessions in the building until 5 p.m.

A priest hears a confession from a woman in the hallways of Madison Square Garden © Reuters / Michael Appleton/The New York Times/POOL

During the mass, Francis combined many traditional aspects of the liturgy with reforms that were implemented as a result of Vatican II. The mass featured prayers in several languages, including Latin. Alongside musical performers such as Gloria Estefan and Jennifer Hudson, the Eucharist was distributed to the sound of Gregorian chants.

During his homily, the pope reflected on finding God during city life.

"God is living in our cities. The church is living in our cities," he said, as quoted by the Guardian. "And God and the church who live in our cities want to be leaven in the dough, and relate to everyone, to stand at everyone’s side while they proclaim the wonders of the mighty counsellor … the prince of peace."