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9/11 anniversary: America remembers lives lost on one of its darkest days

By Faith Karimi and Jason Hanna, CNN

Updated 3:43 PM ET, Fri September 11, 2015

Look back at how September 11 unfolded 09:00

Story highlights

Nearly 3,000 people died in deadliest terrorist attack on American soil
A resilient nation looks to the future while paying tribute to the past

(CNN)With his head bowed during a moment of silence outside the White House, President Barack Obama set the tone Friday for a nation marking a dark day with solemn ceremonies.

Fourteen years ago Friday, terrorists hijacked four passenger planes and rammed two into New York's World Trade Center and a third one into the Pentagon outside Washington.

A fourth jetliner crash-landed on an empty field in Pennsylvania.

By the time the carnage was over, the hijackers had killed 2,977 people in the deadliest terrorist attack on American soil.

People, buildings and planes fell from the sky. Terrified strangers became friends as Americans united on a day that changed the world forever.

On Friday, a resilient nation looked to the future while remembering the past.

Here are the main events that paid tribute to the many lives lost on September 11, 2001:

GROUND ZERO

At the site of the World Trade Center, where most of the victims were, bagpipers and drummers provided solemn tunes to accompany an hours-long ceremony.

A rainbow appears over New York's One World Trade Center on Thursday.

Relatives of those who died stood at podiums at the National September 11 Memorial plaza, reading the names of victims. Each speaker read a block of names before ending with their own loved one, adding a few words of remembrance for their lost sibling, child, parent or cousin.

Moments of silence were observed at the specific times when the planes struck and the buildings fell.

The first plane hit the north tower at 8:46 a.m. The second one struck at 9:03 a.m.

In this attack, 2,753 people died when terrorists intentionally crashed American Airlines Flight 11 and United Airlines Flight 175 into the north and south towers, respectively.

More than 300 firefighters were among those who perished in the attacks and the collapse of the towers. Dozens more were police officers.

PENNSYLVANIA

Hundreds of miles away, a passenger jetliner crashed near Shanksville, Pennsylvania, at 10:03 a.m.

Crowds were to mark a moment of silence at that exact time and read out the names of the victims.

Forty passengers and crew members aboard United Airlines Flight 93 died when the plane crashed into the field. It is believed that the hijackers crashed the plane in that location, rather than their unknown target, after passengers and the crew attempted to retake control.

WASHINGTON

16 photos: 9/11 tributes across the nation

Roses are placed Friday at the National September 11 Memorial in New York before a ceremony commemorating the 14th anniversary of the attacks.

Terry Miller, right, and Chris Miller, center, look for the name of their brother Robert Cromwell Miller at the Empty Sky memorial to New Jersey's victims of 9/11. The memorial is in Jersey City across the Hudson River from the World Trade Center site. Nephew James Miller, left, joins them Friday.

Yachiyo Kuge carries a lantern to place at the Wall of Names at the Flight 93 National Memorial in Shanksville, Pennsylvania, on Thursday, September 10. Kuge is the mother of Toshiya Kuge, a Japanese passenger who died on United Airlines Flight 93 on 9/11. The plane crashed in Pennsylvania as passengers and crew tried to overcome the hijackers.

Some 3,000 flags erected by Pepperdine University students and staff honor the victims of 9/11 on the Malibu, California, on September 10.

A visitor tours the crash site at the Flight 93 National Memorial on September 10. The visitor center complex was dedicated in honor of the victims of Flight 93 on the evening of the 14th anniversary of the 9/11 attacks.

A visitor views a display at the Flight 93 National Memorial visitor center on September 10.

Flags carry the names of the 9/11 victims at Memorial Park in Omaha, Nebraska, on September 10.

<a href="http://www.911memorial.org/blog/look-tribute-light" target="_blank">The Tribute in Light</a> illuminates the sky behind One World Trade Center and the Lower Manhattan skyline on Wednesday, September 9.

The sun rises over Lower Manhattan and One World Trade Center, at left, on Friday, September 11, in a view from Jersey City, New Jersey. The nation is marking the 14th anniversary of 9/11, the deadliest terrorist attack on U.S. soil. Nearly 3,000 people died that day. See other images of 9/11 events:

Gary Mascitis, 14, pays tribute to his uncle during an anniversary ceremony for the attacks in New York. Two hijacked planes hit the World Trade Center on 9/11. A third plane crashed into the Pentagon outside Washington and a fourth into a Pennsylvania field.

American flags are lowered to half-staff at the Washington Monument on September 11.

Honor guards salute during the national anthem in a 9/11 ceremony Friday at Indianapolis International Airport.

Law enforcement officials stand at attention Friday during the national anthem in an anniversary ceremony in New York in commemoration of the 9/11 attacks.

Engine Company 205/Ladder Company 118 in New York's Brooklyn Heights remember the eight firefighters it lost on 9/11, including six who died in their firetruck under the rubble.

President Barack Obama and first lady Michelle Obama lead a moment of silence on the White House South Lawn at 8:46 a.m. Friday -- the time when the first of four hijacked planes hit the World Trade Center on 9/11.

A bugler plays taps during Friday's ceremony on the South Lawn of the White House.

At sunrise a flag was unfurled over the side of the Pentagon, where 184 people were killed when hijacked American Airlines Flight 77 crashed into the building.

Shortly after 9:30 a.m. Friday, a memorial ceremonybegan at the Pentagon Memorial, attended by relatives of the victims. It included wreath laying and remarks by Defense Secretary Ash Carter. Flight 77 hit the Pentagon at 9:37 a.m. on 9/11.

At the White House, President Barack Obama and first lady Michelle Obama stepped onto the South Lawn for a minute of silence at 8:46 a.m. -- the time that the first jet hit the World Trade Center.

Obama made no comment at that observance, but he was later scheduled to visit Fort Meade in Maryland, where he will talk with troops and express his appreciation.

"The President very much values face time with troops -- listening, asking and answering questions, and he looks forward to taking time on the anniversary of 9/11 to engage directly with service members," Pentagon spokesman Peter Cook said.

Outside the Justice Department headquarters in Washington, a crew Friday morning planted a pear tree -- an offspring of a tree at the World Trade Center plaza that survived the buildings' fall. The original tree stands at the 9/11 memorial in New York.

Attorney General Loretta Lynch, speaking at the ceremony, said the tree is a reminder that "we can endure, we can prevail, and we, too, can bloom again."

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