Bob Lewis looks over a field of crosses with names while participating in the College Point Memorial Day Parade in New York, Sunday, May 26, 2013. Lewis made the crosses, 137, for all the service members from College Point that were killed from the Civil War to the Vietnam War. A couple photograph themselves amongst a sea of flags on Boston Common in Boston, Sunday, May 26, 2013. The flags were placed by the Massachusetts Military Heroes Fund in memory of every fallen Massachusetts service member from the Civil War to the present. Joe Schulmann pauses in prayer over a cross bearing the name of his neighbor, Michael Wick, who was killed during the Vietnam War, at the College Point Memorial Day Parade in New York, Sunday, May 26, 2013. Americans planned to gather at cemeteries, memorials and monuments nationwide to honor fallen military service members on Memorial Day, at a time when combat in Afghanistan approaches 12 years and the ranks of World War II veterans dwindles. President Barack Obama was expected to lay a wreath Monday at the Tomb of the Unknowns at Arlington National Cemetery across the Potomac River from Washington. Earlier in the morning, he and first lady Michelle Obama planned to host a breakfast at the White House with "Gold Star" families of service members who have been killed. In one of several ceremonies honoring Americans killed in Afghanistan, the city of South Sioux City, Neb., planned to unveil a statue honoring Navy Petty Officer 1st Class John Douangdara, a dog handler for the SEALs killed in a 2011 helicopter crash. His service dog was also killed in the crash and is memorialized beside him in the statue. At the American Airpower Museum on Long Island, N.Y., a program was planned to honor Women Air Service Pilots, or WASPs, who tested and ferried completed aircraft from factories to bases during World War II. Thirty-eight died during the war, including Alice Lovejoy of Scarsdale, N.Y., who was killed on Sept. 13, 1944, in a midair collision over Texas. "It's very important that we recognize not only their contribution to American history, but women's history," said Julia Lauria-Blum, curator of the WASP exhibit at the museum. These women really blazed a path; they were pioneers for women's aviation. And most important, they gave their lives serving their country and must be honored like anyone else on Memorial Day. Another wreath-laying ceremony was planned at Franklin D. Roosevelt Four Freedoms Park on the southern tip of Roosevelt Island in New York City. The park is a tribute to President Roosevelt's famous speech calling for all people to enjoy freedom of speech, freedom of worship, freedom from want and freedom from fear. In Atlanta, a dedication of the History Center's redone Veterans Park was scheduled for early evening. Soil from major battlefields will be scattered by veterans around the park's flagpole. In suburban Boston, veterans gathered in a park to mark Memorial Day this year rather than hold a parade because of failing health and dwindling numbers. The city of Beverly called off its parade because so few veterans would be able to march. The parade has been a fixture in the town since the Civil War. The holiday weekend also marked the traditional start of the U.S. vacation season. AAA, one of the nation's largest leisure travel agencies, expected 31.2 million Americans to hit the road over the weekend, virtually the same number as last year. Gas prices were about the same as last year, up 1 cent to a national average of $3.65 a gallon Friday.