With our minds focused on beach or pool visits, barbecuing and other activities associated with the unofficial start of summer, it’s easy to overlook what Memorial Day is really all about. Clearly, it is about much more than a fun-filled three-day weekend.

Memorial Day, of course, is a solemn day of remembrance in honor of the men and women who have died while serving in the U.S. armed forces. But how much more do you actually know about the holiday and its origins?

We’ve uncovered some not-so-well-known facts about Memorial Day that you may not be aware of. In fact, we didn’t know about most of them either.

The holiday started during the years following the Civil War to honor both Union and Confederate deaths. It was originally known as Decoration Day.

There is active debate as to where the observance originated. Waterloo, New York, claims to have introduced the holiday on May 5, 1866. That upstate New York community is the clear front-runner in the debate, being that President Lyndon Johnson signed a congressional resolution in 1966 proclaiming Waterloo "The Birthplace of Memorial Day."

Other cities, however, including Charleston, South Carolina; Carbondale, Illinois; Boalsburg, Pennsylvania; Richmond, Virginia; and Columbus, Georgia, continue to stake claims to the title.

In a formal sense, the modern Memorial Day originated with an order issued in 1868 by Union General John A. Logan calling for an official nationwide day of remembrance on May 30.

Originally meant to honor those lost in the Civil War, the southern states observed a different day to memorialize Confederate soldiers who died.

Following World War I, the holiday evolved to commemorate fallen military members in all wars. Currently, however, 11 states still observe an official day to honor Confederate dead. Virginia is the only one to observe Confederate Memorial Day on the same day as Memorial Day.

In 1968, Congress passed the Uniform Monday Holiday Act, establishing Memorial Day as the last Monday in May (rather than May 30). This was done to create a three-day weekend for federal employees.

In 2000, President Bill Clinton signed the National Moment of Remembrance Act, requesting all Americans to pause and observe one minute of silence at 3:00 p.m. local time on Memorial Day.

Many Americans, particularly veterans, government employees and law enforcement officers pay heed to the pause, and a number of organizations observe this special moment, including Major League Baseball, NASCAR and Amtrak (whose trains sound their whistles).

Cities across America host Memorial Day parades, with the largest taking place in New York City, Chicago and Washington, D.C.

More than 250,000 folks turn out for the National Memorial Day Parade in the nation’s capital — an event featuring marching bands, military units, youth groups and floats moving proudly along Constitution Avenue.