Along the parade's route on The Mall, Union flags hung over the crowd barriers or stuck jauntily from headbands, while some fans wrapped themselves in the flag and painted it on their cheeks with face paint.
Some wore T-shirts in the red, white and blue national colours or sequinned tops.
Liam Roddis, a 49-year-old operations manager for a local authority in northern England, opted for a total look with a Union Jack flag suit.
"I'm here for the queen," he said, calling himself "dead proud to be British, dead proud that she's my queen -- for however much longer she is."
In the throng, many had little view of events but said this did not matter.
"We can't see anything but we just wanted to be part of it," said Hilary Matthews, a 70-year-old retired nurse in a Union Jack bowler hat.
For 61-year-old tree surgeon David Hare, the event was a moment of joy after grim world events. He said he has come out for all the royal weddings, too, sometimes sleeping outside the night before.
Among these were 65-year-old Gilbert Falconer, who had come with his wife from Scotland after striking lucky in the national ballot.
"It's like winning the lottery for me," said the ambulance service worker.
"We just want to show our appreciation for what she has done for this country," Falconer said of the queen.
"She's done such an amazing job through her reign.
