She visited the Air Forces memorial at Runnymede, 30 kilometers from London, to mark the centenary of the Royal Australian Air Force.
“It’s been a long time since I was here,” said Elizabeth.
The country has yet to declare a national lockdown, but this week it began to relax some of the sanitary measures imposed to curb the advance of Covid-19.
The 94-year-old monarch is also the queen of Australia and 14 other nations that make up the Commonwealth.
The Commonwealth emerged from the British empire in the middle of the 20th century and the queen has been its chief since her reign began in 1952.
Since the beginning of the year, Elizabeth II had been working remotely from inside Windsor Castle, in the city of the same name, near Runnymede.
In the official residence, the queen is staying with her husband, Prince Philip, 99, who recently spent four weeks in a hospital for health problems.
Elizabeth and Philip were vaccinated against Covid-19 in January this year, as they belong to the priority group for vaccination in the country.
Elizabeth’s last public engagement was in December in Windsor, when she thanked local volunteers and essential workers.
Since the pandemic began in March last year, the queen has rarely left the royal residence.
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