How US will come together to remember 9/11 victims
9/11: What bystanders saw
Americans are marking the 24th anniversary of the September 11, 2001, attacks with solemn ceremonies and tributes honouring nearly 3,000 victims.
Official commemorations are scheduled in New York, at the Pentagon, and in Shanksville, Pennsylvania, with loved ones, dignitaries, and politicians attending.
Ceremonies will include reading victims' names aloud and moments of silence to mark the exact times of the attacks.
Donald Trump and his wife, Melania Trump, will attend the service at the Pentagon, while Vice President JD Vance and his wife, Usha Vance, will be at the World Trade Center site.
Many people are also observing the anniversary through service projects and charity work as part of a national day of service.