9/11 anniversary: National Memorial in New York opens
The New York memorial to those killed on 9/11 is due to open to the public, a day after its dedication on the 10th anniversary of the attacks.
The National 9/11 Memorial will open its doors to several thousand people at 10:00 on Monday (14:00 GMT).
It includes the names of 2,983 people killed by al-Qaeda in New York, the Pentagon and in Pennsylvania.
On Sunday night, President Barack Obama said Americans should honour those who died but look forward with "hope".
He said the decade since the attacks showed the resolve of those in the US to defend their way of life.
The ideal that "men and women should govern themselves... has only been strengthened", Mr Obama said.
Mr Obama was speaking during a memorial concert at the Kennedy Center in Washington, closing a day of official commemorations marking the 10th anniversary of the attacks.
The opening of the memorial in New York will see several thousand visitors each day allowed into the area once occupied by the World Trade Center towers.
Ongoing construction work in the vicinity - most notably of the unfinished One World Trade Center, the new skyscraper being erected by the site - means visitor numbers are being restricted at present.
Visitors are being asked to register in advance for a pass to enter the memorial at a specific time.
The memorial features two huge, deep pools at the base of the old World Trade Center towers.
Around the edges of the pools, each almost an acre in size, the names of those who were killed in the attacks are embossed in bronze panels.
All of the victims' names were read out at Sunday's ceremony, the five-hour reading punctuated by solemn silences, and music.
Bagpipers opened the gathering, the Brooklyn Youth Chorus sang the national anthem, the cellist Yo-Yo Ma performed, and Paul Simon played his classic song The Sound Of Silence.
Mourners placed pictures and flowers beside the names etched in bronze, and relatives of the dead sobbed in grief over the inscriptions.
In the evening, after visiting the field near Shanksville, Pennsylvania, where flight United 93 came down, and attending the Pentagon memorial to lay a wreath, Mr Obama spoke at the Kennedy Center concert.
Much had changed for Americans since 11 September 2001, Mr Obama said.
"We've known war and recession; passionate debates and political divides. We can never get back the lives that were lost on that day, or the Americans who made the ultimate sacrifice in the wars that followed.
"Yet today, it is worth remembering what has not changed," he said.
"Our character as a nation has not changed... Our belief in America, born of a timeless ideal that men and women should govern themselves; that all people are created equal, and deserve the same freedom to determine their own destiny - that belief, through test and trials, has only been strengthened."
Mr Obama paid tribute to the victims of the attacks as well the courage of the survivors.
He also lauded the "two million Americans who have gone to war since 9/11. They have demonstrated that those who do us harm cannot hide from the reach of justice, anywhere in the world."
In the months that followed 9/11, US forces were sent to Afghanistan to oust the Taliban from power for giving sanctuary to al-Qaeda.
In 2003, the US led an invasion of Iraq that overthrew Saddam Hussein.
More than 6,200 members of the US military have been killed in the wars in Iraq and Afghanistan.