Several thousand people turned out at events that included a moment of silence, coordinated with wreath-laying ceremonies at Arlington National Cemetery, where the 35th president is buried, and in his hometown of Boston.
"It seems like we all grew up that day," said Dallas Mayor Mike Rawlings. "Our collective hearts were broken."
“We watched the nightmarish reality that in our front yard, our president had been taken from us, taken from his family, taken from the world," he said. “Out of that tragedy, an opportunity was granted to us."
The moment of silence at 12:30 p.m. CST marked the moment when Lee Harvey Oswald fired at the presidential motorcade from a sixth-story window of the Texas School Book Depository, hitting Kennedy in the head.
With the book depository in the background, the U.S. Navy choir sang "America" and bagpipes played, while 5,000 invitees looked on. An Air Force "missing man" flyover was scheduled, but canceled due to weather.
A new monument to Kennedy was unveiled on the stretch of hillside infamously known as the grassy knoll, including an inscription from the text the president was due to deliver the night of Nov. 22, 1963.
Elsewhere in Dallas, a candlelight vigil was held for police officer J.D. Tippet, a police officer who was killed by Oswald about 45 minutes after Kennedy was assassinated.
And all through the city, bells tolled in remembrance of the president, cut down in his prime.
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