A photo of Princess Diana in a bikini floated around Instagram as a throwback photo during the July Fourth weekend. The photo reportedly was a perfect "Throwback Thursday" photo for the summer.

The classic photo was shared by Giancarlo Giammetti the late princess' friend and Valentino's partner. Taken in 1990, Princess Diana is standing on a yacht owned by fashion designer Valentino who used to frequently dress the royal when she was alive.

In the vintage photo, Princes William and Harry's mother sports a printed two piece bikini with a purple polo shirt covering her upper body. Large sunglasses shield her eyes from the sun as she leans on the railings of the T.M.Blue One yacht.

With her on the picture is a young boy presumed to be a 6-year-old Prince William wearing colorful swimming trunks and a huge grin. Her friend and the Prince of Preslav, Bulgaria's wife Rosario Saxe-Coburg was also captured in the shot.

Giammetti captioned the photo, "Summer is here TBT princess Diana on the TMblue 1990."

The former princess was known to frequent rich friends' boats and yachts according to the Daily Mail. The privacy in those boats offered her freedom from the hounding media and paparazzi that had constantly scrutinized her during most of her adult life.

The "People's Princess"was one of the most iconic royals in Britain, often helping charities and fighting for the rights of her people. She was well-known for her compassion, charm and elegant style and as a result, was a target of a long-standing intense media watch.

She married Prince Charles in 1981 and had her two sons, Princes William and Harry before divorcing in1996, four years after the Prince of Wale's affair with Camilla Parker-Bowles (now his wife) was exposed to the media.

Giammetti, who shared the photo, reportedly had lunch with Diana a few hours before that infamous Paris car crash in 1997. She was killed together with Egyptian mogul Dodi Fayed, whom she was reportedly romantically involved with at that time.