Princess Anne attends Royal Ascot in a look she first wore in 1978

Princess Anne attended the second day of Royal Ascot on Thursday, wearing an outfit she first sported in 1978.

The Princess Royal paired her light blue, button front dress with Peter Pan collar with a white jacket, gloves and a wide-brimmed hat. The look was finished with a triple strand of pearls and a brooch in aquamarine and white diamond.

The jewel is part of the Aquamarine Pineflower tiara set made by Cartier, and used to belong to the Queen Mother.

Her outfit is most remarkable because the Princess first wore the A-line, pleated dress to welcome the president of Botswana to Buckingham Palace alongside her late mother, Queen Elizabeth, in 1978. She wore it again in July last year, for an engagement at the Brompton Cemetery.

Now 72, the Princess is known to favour a sustainable approach to fashion, and has favourite pieces that she returns to many times. In a 2020 interview with Vanity Fair, she even joked that her love of rehashing past looks was rooted in not wanting to spend money.

Sir Seretse Khama, President of Botswwana and Lady Khama with Queen Elizabeth II and Princess Anne at Buckingham Palace in 1978. PA Images

"I still try and buy materials and have them made up [into clothes] because I just think that's more fun," she explained. "It also helps to support those who still manufacture in this country. We mustn't forget we've got those skills, and there are still places that do a fantastic job."

Often described as "Britain's most hardworking Royal" for the number of engagements she undertakes each year, Princess Anne is also a highly accomplished horse woman, having won a team gold medal at the 1972 Olympics, and a team silver medal at the 1988 Olympics.

It is a sport she still enjoys, and perhaps explains the rather remarkable feat of being able to still fit into a dress she first wore 45 years ago.