The U.S. is celebrating Memorial Day to honor its war dead.
President Donald Trump, in his first Memorial Day as the U.S. leader, laid a wreath Monday at the Tomb of the Unknown Soldier at Arlington National Cemetery just outside Washington.
"We honor the noblest among us, the men and women who paid the ultimate price for victory and freedom," Trump said. "They made their sacrifice, not for fame, nor for money, or even for glory, but for country."
Trump said the country's fallen warriors "died in war, so we could live in peace."
He told relatives of those killed in action, "While we cannot know the extent of your pain, what we do know is that our gratitude for them and to you is boundless and undying."
Officially, Memorial Day, observed on the last Monday in May, has been set aside to honor all who died during military service throughout U.S. history.
Observances around the country and Washington are planned for the day.
In Pictures: US Observes Memorial Day
In Pictures: US Observes Memorial Day
Rolling Thunder, with thousands of motorcycle riders in Washington for the holiday, held wreath-laying events at the World War Two Memorial and the Vietnam Veterans Memorial. Rolling Thunder participants ride motorcycles to bring attention to the lingering number of prisoners of war and military service people who are missing in action.
This year, Memorial Day coincides with the 100th anniversary of the birth of America's 35th president — John Fitzgerald Kennedy.
WATCH: World Marks 100th Anniversary of JFK's Birth
Washington's Kennedy Center for the Performing Arts is hosting a JFK Centennial Celebration. Actors Martin Sheen, Brian Dennehy and soprano Renee Fleming are among the artists participating in the event.
