Former US presidents Barack Obama and George W. Bush will lead mourners on Saturday in a service for the late John McCain, the longtime Arizona senator and Vietnam war hero whose bids for the White House were dashed by the two men.
On the way to Washington's National Cathedral, the cortege of America's most famous prisoner of war will stop at the Vietnam Veterans Memorial where his wife Cindy will lay a wreath to honour those who died in the war.
Obama and Bush will be joined by a collection of former US presidents, senators, Vietnam-era officials and others paying tribute to the statesman who died on August 25 of brain cancer, days shy of his 82nd birthday.
He served in Congress for decades, but it was his military service, punctuated by years as a prisoner of war in North Vietnam, that shaped McCain's political life.
Shot down over Hanoi while on a bombing mission in 1967, McCain was held as a prisoner until 1973 and tortured by his North Vietnamese captors in a jail that Americans dubbed the "Hanoi Hilton."
Conspicuously absent from the service will be President Donald Trump, who over the past three years engaged in a public feud with McCain.
McCain's family had made clear that Trump was not welcome.
Inside the cathedral, the congregants will also hear from a central figure of the Vietnam War: 95-year-old Henry Kissinger.
Pallbearers for Saturday's service reflect the eclectic political company McCain kept.
It include Hollywood actor and liberal political activist Warren Beatty, former New York City Mayor Michael Bloomberg, liberal former Senator Russ Feingold and former Senator Gary Hart.
