Memorial Day began as a tradition of honoring America’s fallen soldiers after the Civil War by placing fresh flowers upon their graves. Originally known as Decoration Day, it was recognized as a holiday in every state by 1890, and Congress made it a federal holiday on the last Monday of May effective in 1971.

The day honors the more than 1.3 million military service members who died serving their country in America’s wars dating back to the American Revolution.

But many also mark the occasion by acknowledging the country’s nearly 16 million U.S. military veterans and 1.3 million active duty troops who put their lives at risk serving their country.

America’s service members may be buried in the country’s National Cemeteries overseen by the Department of Veterans Affairs. There are four in the Bay Area: San Francisco National Cemetery on Lincoln Boulevard in San Francisco, Golden Gate National Cemetery on Sneath Lane in San Bruno, Mare Island Naval Cemetery on Imhoff Road in Vallejo, and Benicia Arsenal Post Cemetery on Birch Lane in Benicia. These are no longer available for new burial sites. There also is the VA grant-funded California Central Coast Veterans Cemetery on Parker Flats Road in Seaside, open to new burials.

The Bay Area is home to many veterans. Solano County, with many retired military living near Travis Air Force Base east of Fairfield, has the highest concentration of veterans in the region, with 8.3% of the adult population being former service members, more than twice the regional average, according to the U.S. Census available data.

Contra Costa, Napa and Sonoma counties also have higher veteran populations around the Bay, while they are a smaller share of their communities in San Francisco and Santa Clara County.

Veterans from the Vietnam War era are the most numerous around the Bay Area, about 80,000, followed by those from the more recent wars in the Middle East.

But there also are a number of older vets who served their country during the Korean War and even 4,400 from World War II.

Many will spend today reflecting on fallen comrades who didn’t come home.