A new exhibit features Princess Diana’s wedding gown, but there’s another garment from her big day on show with a fascinating background.

The exhibition Royal Style in the Making opens today at Kensington Palace, Diana’s old residence.

Visitors will be able to view her famous Elizabeth and David Emanuel bridal gown, complete with a spectacular 25-foot train, as well as another outfit the royal wore on her 1981 wedding day: a peach ensemble to depart with Prince Charles aboard the Royal Yacht Brittania for their honeymoon journey to Gibraltar.

Curator Matthew Storey explained how Diana’s collaboration with designer Bellville Sassoon “almost didn’t happen” during a special preview showing before of the launch.

Princess Diana had recently gotten engaged to Prince Charles and was searching for an attire for her formal engagement photographs when she first visited the Bellville Sassoon store. It was almost closing hours, and Diana was having trouble finding anything she liked. The sales clerk, who did not recognize Diana, informed her that Harrod’s department store was “is just around the corner.”

“You can imagine how Belinda [Bellville] and David [Sassoon] felt when they realized the future Princess of Wales had been turned away,” Matthew allegedly said.

However, Diana quickly returned and selected the blue and white outfit she wore on February 24, 1981.

The label went on to produce several ensembles for Princess Diana, including the peach ensemble on exhibit, which is paired with an original drawing by designer David Sassoon. Storey said that depending on the weather, two versions of the costume were created: one with short sleeves and one with longer sleeves.

According to The Times, David Sassoon remembered, “When she got engaged, her mother brought her in to us and asked us to make the going-away outfit”, whilst he opened up about the late Princess Diana’s thoughtfulness when it came to wearing Bellville Sassoon designs.

“She was very thoughtful when she received a dress, and if it had been a success she would always write or telephone and say, ‘That dress was wonderful, I enjoyed wearing it,’ that everyone at Balmoral or Buckingham Palace or wherever the occasion was that she wore it was very enthusiastic about it,” he revealed. “She was wonderful at saying a big thank you.”

The gown is on display in the newly renovated Orangery on the royal grounds, with original drawings, fabric samples, and handwritten notes used by designers such as David and Elizabeth Emanuel, Norman Hartnell, and Sassoon.

Royal Style in the Making features Princess Diana’s wedding gown for the first time in almost 25 years. It was originally shown in July 1998 at Diana’s ancestral home, Althorp, almost a year after the royal’s sad death.