Nation holds somber 1 minute of silence
A national minute of silence was held at 10 a.m. ET ahead of the service.
Heathrow Airport said it was stopping all arrivals and departures for six minutes to coincide with the national minute of silence.
"During the funeral service no Heathrow arrivals or departures will fly over the area, but we don’t expect this to require any rerouting of aircraft," the airport said.
The flowers in the wreath on the Duke of Edinburgh's coffin were chosen by the Queen.
The coffin was topped by Philip's Admiral of the Fleet Naval Cap and a sword given to him by his father-in-law, King George VI, for his 1947 wedding to then-Princess Elizabeth.
The funeral is at St George's Chapel, where Harry and Meghan Markle married in May 2018.