The Queen and Duke of Edinburgh are in Malta for a three-day tour of the island where they once lived.
The royal couple were resident there as newlyweds before the Queen's accession to the throne, and celebrated their 60th wedding anniversary there in 2007.
The monarch will open the Commonwealth Heads of Government Meeting (Chogm) in the capital Valletta during the visit.
British High Commissioner to Malta Rob Luke said the Royal Family had an "enduring affection" for the island.
The Queen and duke were greeted by Malta's Prime Minister Joseph Muscat at the airport ahead of a ceremonial welcome, attended by President Marie-Louise Coleiro Preca.
This was due to be held in the capital Valletta but has been moved due to bad weather, and took place instead inside the presidential palace in Attard.
The couple will be meeting some former associates from the time they spent on the Mediterranean island, from 1949 to 1951, during the visit.
By Nicholas Witchell, royal correspondent, BBC News
Nowhere outside the United Kingdom, it has been suggested, holds happier personal memories for the Queen than the small Mediterranean island of Malta.
It was to Malta that she came to live for nearly two years in 1949. They were comparatively carefree times. She was then a 23-year-old princess. The burdens of the crown were then nearly three years in the future.
She was two years into her marriage to a young naval officer, Philip Mountbatten. He'd been posted to Britain's then naval base in Malta. They left their one small child, Charles, with Elizabeth's parents, King George VI and his wife.
It has been said that it was the one and perhaps only opportunity that Elizabeth had to lead a comparatively "normal" life as the wife of a serving naval officer. They lived in Villa Guardamangia near the capital Valletta and were able to move about with a degree of freedom that was never to be repeated.
It all changed in February 1952 when George VI died unexpectedly and Elizabeth succeeded to the throne. Her life since then has been constrained by the formalities, scrutiny and ever-tighter security that are the inescapable accompaniment to her role as queen and head of state.
So on this brief visit to Malta to open the 24th conference of Commonwealth heads of government she may perhaps - in amongst all the demands of duty - recall with some nostalgia that brief glimpse of "ordinary" life that Malta afforded her.
President Coleiro Preca presented the couple with a watercolour of Villa Guardamangia, their former home on the island, by a local artist.
In an exchange of gifts, the Queen gave the president a gold lace tablecloth from Nottinghamshire and a Royal Crown Derby fruit bowl, while the president's husband Edgar was handed a hamper from the Windsor farm shop.
The Queen is being accompanied by the Prince of Wales and Duchess of Cornwall on the tour.
The duchess has visited the Mdina Glass store in Ta' Qali, a traditional glass blowing factory and shop.
"This is what I call retail therapy," she said. "I haven't done any Christmas shopping yet."
It will be the fourth time Charles, who is due to make a speech on climate change at a business forum, has attended Chogm.
The monarch will open the event on Friday with a speech to the Commonwealth leaders and attend a banquet that evening.
UK Prime Minister David Cameron and Foreign Secretary Philip Hammond are expected to attend the meeting.
Mr Cameron wants discussions to focus on ways Commonwealth countries can work together to defeat terrorist groups.