Under a canopy of trees, a solemn crowd gathered Monday in Washington Square Park to celebrate Memorial Day, not by reading a book on the benches or dipping their feet in the fountain, but by honoring America's first fallen soldiers.

As they have for decades, organizers from the Daughters of the American Revolution and other patriotic organizations came to Philadelphia's Tomb of the Unknown Soldier to lay a wreath in recognition of casualties of that war and others that followed.

The park is a lunchtime getaway to many. It is also hallowed ground where thousands of soldiers from the Revolutionary War were hastily buried in unmarked graves.

To signal the ceremony's opening, a bugle played over the sound of splashing water - fortunately from the nearby fountain and not rain that had threatened but never fell, sparing a number of memorial celebrations held throughout Philadelphia.

At the Philadelphia Vietnam Veterans Memorial at Spruce Street and Columbus Boulevard, the names of two career noncommissioned officers who became ill in Vietnam and later died in military hospitals were unveiled in a special ceremony.

Master Sgt. Francis G. Corcoran, a Port Richmond native, and Master Sgt. George L. Wilson, a 1948 graduate of Frankford High School, were approved in 2013 by the Department of Defense for inclusion at the Vietnam Veterans Memorial in Washington and were added to that "Wall" last May. Their inclusion Monday at the Philadelphia Vietnam Veterans Memorial brought to 648 the total Philadelphians honored there.

In Washington Square Park on Monday, Bobbi McMullen, Pennsylvania regent with the Daughters of the American Revolution, said the wreath-laying honored all men and women who died in service, but "of course, the Revolutionary War ones are our first ones."

Sporting a red-white-and-blue sash over a dark-blue dress, Nancy Popielarski sang the national anthem.

"This is the day to remember that somebody gave everything," she said. "They gave their lives and their fortunes."

Popielarski checks off a couple of historical boxes - as a descendant of a Revolutionary War soldier and as the governor of the New Jersey State Society of Mayflower Descendants. (One of her ancestors was born on the vessel.)

Visiting from Atlanta, Robbie Ooten learned of the wreath ceremony at the last minute and made it a point to attend. The music teacher also is a descendant of a Revolutionary War soldier, she said.

Noting the historical importance of the tribute, Ooten said, "I wouldn't have the freedom I have." She said she was concerned that her students might not understand the ultimate sacrifice that many have made.

"So many kids now, they don't really get patriotism," she said.

By the time America's War of Independence broke out in 1775, Washington Square - then known as Southeast Square - was already doubling as a potter's field. A swelling number of soldiers gravely wounded or afflicted by disease necessitated mass graves that ran the length of the square.

In states such as Pennsylvania, many of those soldiers were young and poor, and some were recent immigrants.

The city erected the memorial in the late 1950s. Among its inscriptions: Freedom is a light for which many men have died in darkness.

"It's important that people know this," said Patricia Coyne, of the Flag House chapter of the Daughters of the American Revolution. "They're walking amongst all of this, and they don't even know it."