Nearly four million visitors come to Arlington National Cemetery each year. Most come to pay respect to their loved ones, to honor the leaders interred here, or to thank the more than 300,000 people buried here, many of whom were soldiers killed in the line of duty.
The original 200 acres were designated as a military cemetery on June 15, 1864. Soldiers and veterans from every war the United States has fought, from the Revolutionary War to the war in Iraq, are buried here (those who died prior to the Civil War were reinterred in Arlington after 1900). Three unknown soldiers--from World War I, World War II, and the Korean War-- are buried at the never-officially-named Tomb of the Unknowns. (The Vietnam veteran who had been buried here was identified in 1998, and his body was returned to his family in St. Louis.)
President John F. Kennedy is buried in Arlington. His grave is marked by the Eternal Flame, designed so that a constant spark of electricity ignites the gas, keeping the flame alive through rain and wind.