The event on Saturday sees the entertainment complex throw open its doors for visitors to get a back stage look at some of the venue’s hidden treasures.
Legendary crooner Frank Sinatra played Blackpool Opera House on July 16 1950 and July 26 1953.
And on Saturday, for the first time since, the 1953 concert can be relived and heard in its original setting, having been recorded privately.
The hour-long recording will begin at 1pm, between demonstrations of the Opera House’s Wurlitzer organ.
A spokesman said: “You will be able to sit in the auditorium and try to imagine you are there back in 1953 listening to Frank Sinatra live.
“A slideshow of historical posters and programmes, will be shown in the Pavilion Theatre, taking guests on a journey back in time, bringing to life bygone days of Blackpool’s most magnificent venue – guests will also have the opportunity to learn more about the restorations taking place and new conference and exhibition centre currently in development.
“Throughout the day, guests can explore every nook and cranny of the world-famous Grade II* listed building during this exclusive access all areas event - treading the Opera House boards and viewing rooms where stars and world leaders have gone before them.
“Resident experts Ted and Anne Lightbown will be on hand in the Floral Hall to answer questions about the illustrious building’s 140-year history.”
Doors open from 11am until 3pm. Free entry.