Eighteen years after the deadliest terror attack on U.S. soil, Americans across the nation, including in San Diego, came together with the same promise -- to "never forget" the thousands of lives lost on Sept. 11, 2001.
Commemoration ceremonies in San Diego began last week, when hundreds of volunteers climbed 110 flights of stairs at the Bayfront Hilton Hotel to honor the first responders who sacrificed their lives to save thousands of people from the World Trade Center.
"It’s one of those things you have to do because you can’t ever forget what happened in the past," said Palomar Airport Firefighter Ryan Grophe.
Traffic was halted for three to six minutes at all land Ports of Entry on the U.S.-Mexico border on Wednesday starting at 5:46 a.m. -- the moment the first plane struck the north tower. U.S. Customs and Border Protection commemorated the tragedy with a moment of silence.
The Veterans Museum in Balboa Park tolled their Freedom Bell at least 2,977 times -- one for each of the lives lost when an aircraft crashed and the trade center's twin towers fell.
The bronze-casted bell is one of San Diego's connections to Sept. 11; the bell is made with 11 pounds of iron from the trade center.
The ceremony symbolically began at 8:46 a.m., to coincide with the time in which the first plane struck the north tower.
Local first responders stood at attention outside the Coronado Fire Station early Wednesday to pay tribute to the 343 firefighters who died on September 11 and several others who later died from 9/11-related illnesses.
Nearby, children wrote thank you cards to the firefighters who ran into the building during the tragedy, not knowing the outcome of that fateful day.
It has become a tradition in San Diego for retired New York firefighters to pay their respects aboard USS Midway, and that tradition continued Wednesday. The ceremony included a tolling of the bells by San Diego Fire-Rescue firefighters, an emergency helicopter flyover and a 21-gun salute.
The commemorative event began in 2006, when the San Diego Chapter of the retired New York Firefighters asked museum officials if they could hold a 9/11 memorial aboard the historic Navy vessel.
And, a traveling tribute to the victims of 9/11 made its way to Liberty Station. The San Diego Fire-Rescue Department was presented with a piece of artwork that has been spending months at fire houses across San Diego County during a four-year journey.
The commemorative artwork raises money for the families of fallen firefighters and has spent time with firefighters in Encinitas, San Marcos, Carlsbad, La Mesa, Santee and Fallbrook, among others.
San Diego's ceremonies will coincide with others across the nation. At New York's ground zero, all 2,977 victims' names are read aloud. For more on those, click here.
Remembering Those Lost
Several San Diegans were among those killed when terrorists hijacked and crashed four airplanes. Two planes were flown into the World Trade Center towers in New York, one crashed into the Pentagon and the last crashed in a field in Pennsylvania.
Deora Bodley, a 20-year-old college student from Mira Mesa, was visiting friends in New Jersey before boarding United Flight 93. A graduate of La Jolla Country Day, Bodley was about to start her junior year at the University of Santa Clara.
"Deora Frances Bodley would be 38 years old today. That day, she was the youngest passenger on board," Former Pennsylvania Gov. Mark Schweiker said at the Flight 93 National Memorial in Shanksville, Pennsylvania Tuesday."
The 33 passengers and 7 crew members aboard Flight 93 have been marked as heroes who sacrificed their own lives to thwart what could have been an even greater terror attack.
Brian Sweeney, a one-time Pacific Beach resident, was aboard Flight 175 on that fateful day and managed to leave his wife a voicemail moments before he died that begins, "Hi Jules, it's Brian. Listen, I'm on an airplane that's been hijacked."
Susie Ward Baker of La Mesa lost her son, 38-year-old Tim Ward, a project manager for Rubios and 1987 graduate of San Diego State University. He was also on Flight 175.
Ramona resident Ann Browne was anticipating a visit from her brother Father Francis Grogan from Massachusetts. A friend had given him a first-class ticket on the United flight.
Robert Penninger, 63, of Poway was on American Airlines Flight 77 when it crashed into the Pentagon. A classic car and motorcycle enthusiast, Penninger was said to enjoy showing his 1999 Cobra Mustang at area car shows.
Stock trader Brent Woodall, the son of a La Jolla couple, called his parents from Tower 2 when the first plane crashed into the WTC. He called again later to say he was getting out but he perished in the tower collapse.
Woodall graduated La Jolla High School where a memorial award and scholarship was created to recognize outstanding baseball players, something Woodall excelled at before beginning a career in finance.
Across the Nation
The 9/11 commemorations are by now familiar rituals, centered on reading the names of the dead. But each year at ground zero, victims' relatives infuse the ceremony with personal messages of remembrance, concern and inspiration.
A crowd of victims' relatives is expected at ground zero Wednesday, while President Donald Trump is scheduled to join an observance at the Pentagon. Vice President Mike Pence is to speak at the third attack site, near Shanksville, Pennsylvania.
Former President George W. Bush, the commander-in-chief at the time of the 2001 attacks, is due at an afternoon wreath-laying at the Pentagon.