Adam Gopnik grew up in Canada, where he saw the Queen age gracefully on the country's bank notes - though he says the royal connection often felt vague. Arriving in London this week amid union flags and flowers, Adam reflects on the constancy of the Queen's reign.

"What lasts for seventy years," he writes, "and never takes a turn into indecency or becomes cruel or sordid in any of the obvious ways has my vote. Well, not my vote, obviously....my allegiance. Well, okay, not my allegiance... my admiration."

Producer: Adele Armstrong
Sound: Nigel Appleton
Production coordinator: Gemma Ashman
Editor: Richard Fenton-Smith