It would have been Diana’s 60th birthday on July 1.
The exhibition coincides with a statue of Diana, which is being unveiled in Kensington Palace’s Sunken Garden.
Matthew Storey, the curator of Royal Style in the Making, said: “Her style is being celebrated again.”
Made of ivory silk taffeta and antique lace, the dress was valued at £9,000 at the time of the wedding.
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